Digital camera with printing assembly

ABSTRACT

A digital camera includes an image capture assembly, roll of print media and microelectromechanical stationary printhead. Upon capturing an image a central processing integrated circuit operates the printhead and associated transport assembly to print the captured image. A guillotine is provided to automatically severe each print. The guillotine operates a counter in order that an operator of the digital camera is able to keep track of how much print media remains on the roll.

This is a Continuation application of U.S. Ser. No. 10/729,151 filed on Dec. 8, 2003 which is a continuation of Ser. No. 09/112,774 filed on Jul. 10, 1998 all of which are herein incorporated by reference.

FIELD OF THE INVENTION

The present invention relates substantially to the concept of a disposable camera having instant printing capabilities and in particular, discloses an image capture and processing device for a digital camera system.

BACKGROUND OF THE INVENTION

Recently, the concept of a “single use” disposable camera has become an increasingly popular consumer item. Disposable camera systems presently on the market normally include an internal film roll and a simplified gearing mechanism for traversing the film roll across an imaging system including a shutter and lensing system. The user, after utilising a single film roll returns the camera system to a film development centre for processing. The film roll is taken out of the camera system and processed and the prints returned to the user. The camera system is then able to be re-manufactured through the insertion of a new film roll into the camera system, the replacement of any worn or wearable parts and the re-packaging of the camera system in accordance with requirements. In this way, the concept of a single use “disposable” camera is provided to the consumer.

Recently, a camera system has been proposed by the present applicant which provides for a handheld camera device having an internal print head, image sensor and processing means such that images sense by the image sensing means, are processed by the processing means and adapted to be instantly printed out by the printing means on demand. The proposed camera system further discloses a system of internal “print rolls” carrying print media such as film on to which images are to be printed in addition to ink to supplying the printing means for the printing process. The print roll is further disclosed to be detachable and replaceable within the camera system.

Unfortunately, such a system is likely to only be constructed at a substantial cost and it would be desirable to provide for a more inexpensive form of instant camera system which maintains a substantial number of the quality aspects of the aforementioned arrangement.

It would be further advantageous to provide for the effective interconnection of the sub components of a camera system.

SUMMARY OF THE INVENTION

In accordance with a first aspect of the invention, there is provided an image capture and processing device which comprises

-   -   an image sensor integrated circuit;     -   a plurality of analogue-to-digital converters (ADC's) that are         connected to the image sensor integrated circuit to convert         analogue signals generated by the image sensor integrated         circuit into digital signals;     -   image processing circuitry that is connected to the ADC's to         carry out image processing operations on the digital signals and     -   a print head interface that is connected to the image processing         circuitry to receive data from the image processing circuitry         and to format that data correctly for a printhead.

A memory device may be interposed between the image sensor integrated circuit and the image processing circuitry to store data relating to an image sensed by the image sensor integrated circuit.

The image sensor integrated circuit may define a CMOS active pixel sensor array. The image sensor integrated circuit may incorporate a plurality of analog signal processors that are configured to carry out enhancement processes on analog signals generated by the active pixel sensor array.

The image processing circuitry may include color interpolation circuitry to interpolate pixel data. The image processing circuitry may include convolver circuitry that is configured to apply a convolution process to the image data.

The print head interface may be configured to format the data correctly for a pagewidth printhead.

The device may be a single integrated circuit.

The invention extends to a camera system that includes an image capture and processing device as described above.

In accordance with a second aspect of the present invention, there is provided in a camera system comprising: an image sensor device for sensing an image; a processing means for processing the sensed image; a print media supply means for the supply of print media to a print head; a print head for printing the sensed image on the print media stored internally to the camera system; a portable power supply interconnected to the print head, the sensor and the processing means; and a guillotine mechanism located between the print media supply means and the print head and adapted to cut the print media into sheets of a predetermined size.

Further, preferably, the guillotine mechanism is detachable from the camera system. The guillotine mechanism can be attached to the print media supply means and is detachable from the camera system with the print media supply means. The guillotine mechanism can be mounted on a platen unit below the print head.

BRIEF DESCRIPTION OF THE DRAWINGS

Notwithstanding any other forms which may fall within the scope of the present invention, preferred forms of the invention will now be described, by way of example only, with reference to the accompanying drawings in which:

FIG. 1 illustrates a front perspective view of the assembled camera of the preferred embodiment;

FIG. 2 illustrates a rear perspective view, partly exploded, of the preferred embodiment;

FIG. 3 is a perspective view of the chassis of the preferred embodiment;

FIG. 4 is a perspective view of the chassis illustrating mounting of electric motors;

FIG. 5 is an exploded perspective of the ink supply mechanism of the preferred embodiment;

FIG. 6 is rear perspective of the assembled form of the ink supply mechanism of the preferred embodiment;

FIG. 7 is a front perspective view of the assembled form of the ink supply mechanism of the preferred embodiment;

FIG. 8 is an exploded perspective view of the platen unit of the preferred embodiment;

FIG. 9 is a perspective view of the assembled form of the platen unit;

FIG. 10 is also a perspective view of the assembled form of the platen unit;

FIG. 11 is an exploded perspective view of the printhead recapping mechanism of the preferred embodiment;

FIG. 12 is a close up exploded perspective of the recapping mechanism of the preferred embodiment;

FIG. 13 is an exploded perspective of the ink supply cartridge of the preferred embodiment;

FIG. 14 is a close up perspective, view partly in section, of the internal portions of the ink supply cartridge in an assembled form;

FIG. 15 is a schematic block diagram of one form of integrated circuit layer of the image capture and processing integrated circuit of the preferred embodiment;

FIG. 16 is an exploded view perspective illustrating the assembly process of the preferred embodiment;

FIG. 17 illustrates a front exploded perspective view of the assembly process of the preferred embodiment;

FIG. 18 illustrates a perspective view of the assembly process of the preferred embodiment;

FIG. 19 illustrates a perspective view of the assembly process of the preferred embodiment;

FIG. 20 is a perspective view illustrating the insertion of the platen unit in the preferred embodiment;

FIG. 21 illustrates the interconnection of the electrical components of the preferred embodiment;

FIG. 22 illustrates the process of assembling the preferred embodiment; and

FIG. 23 is a perspective view further illustrating the assembly process of the preferred embodiment.

DESCRIPTION OF PREFERRED AND OTHER EMBODIMENTS

Turning initially simultaneously to FIG. 1 and FIG. 2 there are illustrated perspective views of an assembled camera constructed in accordance with the preferred embodiment with FIG. 1 showing a front perspective view and FIG. 2 showing a rear perspective view. The camera 1 includes a paper or plastic film jacket 2 which can include simplified instructions 3 for the operation of the camera system 1. The camera system 1 includes a first “take” button 4 which is depressed to capture an image. The captured image is output via output slot 6. A further copy of the image can be obtained through depressing a second “printer copy” button 7 whilst an LED light 5 is illuminated. The camera system also provides the usual view finder 8 in addition to a CCD image capture/lensing system 9.

The camera system 1 provides for a standard number of output prints after which the camera system 1 ceases to function. A prints left indicator slot 10 is provided to indicate the number of remaining prints. A refund scheme at the point of purchase is assumed to be operational for the return of used camera systems for recycling.

Turning now to FIG. 3, the assembly of the camera system is based around an internal chassis 12 which can be a plastic injection molded part. A pair of paper pinch rollers 28, 29 utilized for decurling are snap fitted into corresponding frame holes eg. 26, 27.

As shown in FIG. 4, the chassis 12 includes a series of mutually opposed prongs eg. 13, 14 into which is snapped fitted a series of electric motors 16, 17. The electric motors 16, 17 can be entirely standard with the motor 16 being of a stepper motor type. The motor 16, 17 include cogs 19, 20 for driving a series of gear wheels. A first set of gear wheels is provided for controlling a paper cutter mechanism and a second set is provided for controlling print roll movement.

Turning next to FIGS. 5 to 7, there is illustrated an ink supply mechanism 40 utilized in the camera system. FIG. 5 illustrates a back exploded perspective view, FIG. 6 illustrates a back assembled view and FIG. 7 illustrates a front assembled view. The ink supply mechanism 40 is based around an ink supply cartridge 42 which contains printer ink and a print head mechanism for printing out pictures on demand. The ink supply cartridge 42 includes a side aluminium strip 43 which is provided as a shear strip to assist in cutting images from a paper roll.

A dial mechanism 44 is provided for indicating the number of “prints left”. The dial mechanism 44 is snap fitted through a corresponding mating portion 46 so as to be freely rotatable.

As shown in FIG. 6, the mechanism 40 includes a flexible PCB strip 47 which interconnects with the print head and provides for control of the print head. The interconnection between the Flex PCB strip and an image sensor and print head integrated circuit can be via Tape Automated Bonding (TAB) Strips 51, 58. A moulded aspherical lens and aperture shim 50 (FIG. 5) is also provided for imaging an image onto the surface of the image sensor integrated circuit normally located within cavity 53 and a light box module or hood 52 is provided for snap fitting over the cavity 53 so as to provide for proper light control. A series of decoupling capacitors eg. 34 can also be provided. Further a plug 45 (FIG. 7) is provided for re-plugging ink holes after refilling. A series of guide prongs eg. 55-57 are further provided for guiding the flexible PCB strip 47.

The ink supply mechanism 40 interacts with a platen unit 60 which guides print media under a printhead located in the ink supply mechanism. FIG. 8 shows an exploded view of the platen unit 60, while FIGS. 9 and 10 show assembled views of the platen unit. The platen unit 60 includes a first pinch roller 61 which is snap fitted to one side of a platen base 62. Attached to a second side of the platen base 62 is a cutting mechanism 63 which traverses the platen unit 60 by means of a rod 64 having a screw thread which is rotated by means of cogged wheel 65 which is also fitted to the platen base 62. The screw threaded rod 64 mounts a block 67 which includes a cutting wheel 68 fastened via a fastener 69. Also mounted to the block 67 is a counter actuator which includes a pawl 71 The pawl 71 acts to rotate the dial mechanism 44 of FIG. 6 upon the return traversal of the cutting wheel. As shown previously in FIG. 6, the dial mechanism 44 includes a cogged surface which interacts with pawl 71, thereby maintaining a count of the number of photographs by means of numbers embossed on the surface of dial mechanism 44. The cutting mechanism 63 is inserted into the platen base 62 by means of a snap fit via clips 74.

The platen unit 60 includes an internal recapping mechanism 80 for recapping the print head when not in use. The recapping mechanism 80 includes a sponge portion 81 and is operated via a solenoid coil so as to provide for recapping of the print head. In the preferred embodiment, there is provided an inexpensive form of printhead recapping mechanism provided for incorporation into a handheld camera system so as to provide for printhead recapping of an inkjet printhead.

FIG. 11 illustrates an exploded view of the recapping mechanism whilst FIG. 12 illustrates a close up of the end portion thereof The re-capping mechanism 80 is structured around a solenoid including a 16 turn coil 75 which can comprise insulated wire. The coil 75 is turned around a first stationery solenoid arm 76 which is mounted on a bottom surface of the platen base 62 (FIG. 8) and includes a post portion 77 to magnify effectiveness of operation. The arm 76 can comprise a ferrous material.

A second moveable arm 78 of the solenoid actuator is also provided. The arm 78 is moveable and is also made of ferrous material. Mounted on the arm is a sponge portion surrounded by an elastomer strip 79. The elastomer strip 79 is of a generally arcuate cross-section and act as a leaf spring against the surface of the printhead ink supply cartridge 42 (FIG. 5) so as to provide for a seal against the surface of the printhead ink supply cartridge 42. In the quiescent position an elastomer spring unit 87, 88 acts to resiliently deform the elastomer seal 79 against the surface of the ink supply unit 42.

When it is desired to operate the printhead unit, upon the insertion of paper, the solenoid coil 75 is activated so as to cause the arm 78 to move down to be adjacent to the end plate 76. The arm 78 is held against end plate 76 while the printhead is printing by means of a small “keeper current” in coil 75. Simulation results indicate that the keeper current can be significantly less than the actuation current. Subsequently, after photo printing, the paper is guillotined by the cutting mechanism 63 of FIG. 8 acting against Aluminium Strip 43, and rewound so as to clear the area of the re-capping mechanism 80. Subsequently, the current is turned off and springs 87, 88 return the arm 78 so that the elastomer seal is again resting against the printhead ink supply cartridge.

It can be seen that the preferred embodiment provides for a simple and inexpensive means of re-capping a printhead through the utilisation of a solenoid type device having a long rectangular form. Further, the preferred embodiment utilises minimal power in that currents are only required whilst the device is operational and additionally, only a low keeper current is required whilst the printhead is printing.

Turning next to FIGS. 13 and 14, FIG. 13 illustrates an exploded perspective of the ink supply cartridge 42 whilst FIG. 14 illustrates a close up sectional view of a bottom of the ink supply cartridge with the printhead unit in place. The ink supply cartridge 42 is based around a pagewidth printhead 102 which comprises a long slither of silicon having a series of holes etched on the back surface for the supply of ink to a front surface of the silicon wafer for subsequent ejection via a micro electro mechanical system. The form of ejection can be many different forms such as those set out in the tables below.

Of course, many other inkjet technologies, as referred to the attached tables below, can also be utilised when constructing a printhead unit 102. The fundamental requirement of the ink supply cartridge 42 is the supply of ink to a series of colour channels etched through the back surface of the printhead 102. In the description of the preferred embodiment, it is assumed that a three colour printing process is to be utilised so as to provide full colour picture output. Hence, the print supply unit includes three ink supply reservoirs being a cyan reservoir 104, a magenta reservoir 105 and a yellow reservoir 106. Each of these reservoirs is required to store ink and includes a corresponding sponge type material 107-109 which assists in stabilising ink within the corresponding ink channel and inhibiting the ink from sloshing back and forth when the printhead is utilised in a handheld camera system. The reservoirs 104, 105, 106 are formed through the mating of first exterior plastic piece 110 and a second base piece 111.

At a first end 118 of the base piece 111 a series of air inlet 113-115 are provided. Each air inlet leads to a corresponding winding channel which is hydrophobically treated so as to act as an ink repellent and therefore repel any ink that may flow along the air inlet channel. The air inlet channel further takes a convoluted path assisting in resisting any ink flow out of the chambers 104-106. An adhesive tape portion 117 is provided for sealing the channels within end portion 118.

At the top end, there is included a series of refill holes (not shown) for refilling corresponding ink supply chambers 104, 105, 106. A plug 121 is provided for sealing the refill holes.

Turning now to FIG. 14, there is illustrated a close up perspective view, partly in section through the ink supply cartridge 42 of FIG. 13 when formed as a unit. The ink supply cartridge includes the three colour ink reservoirs 104, 105, 106 which supply ink to different portions of the back surface of printhead 102 which includes a series of apertures 128 defined therein for carriage of the ink to the front surface.

The ink supply cartridge 42 includes two guide walls 124, 125 which separate the various ink chambers and are tapered into an end portion abutting the surface of the printhead 102. The guide walls 124, 125 are further mechanically supported by block portions eg. 126 which are placed at regular intervals along the length of the ink supply unit. The block portions 126 leave space at portions close to the back of printhead 102 for the flow of ink around the back surface thereof.

The ink supply unit is preferably formed from a multi-part plastic injection mould and the mould pieces eg. 110, 111 (FIG. 13) snap together around the sponge pieces 107, 109. Subsequently, a syringe type device can be inserted in the ink refill holes and the ink reservoirs filled with ink with the air flowing out of the air outlets 113-115. Subsequently, the adhesive tape portion 117 and plug 121 are attached and the printhead tested for operation capabilities. Subsequently, the ink supply cartridge 42 can be readily removed for refilling by means of removing the ink supply cartridge, performing a washing cycle, and then utilising the holes for the insertion of a refill syringe filled with ink for refilling the ink chamber before returning the ink supply cartridge 42 to a camera.

Turning now to FIG. 15, there is shown an example layout of the Image Capture and Processing integrated circuit (ICP) 48.

The Image Capture and Processing integrated circuit 48 provides most of the electronic functionality of the camera with the exception of the print head integrated circuit. The integrated circuit 48 is a highly integrated system. It combines CMOS image sensing, analog to digital conversion, digital image processing, DRAM storage, ROM, and miscellaneous control functions in a single integrated circuit.

The integrated circuit is estimated to be around 32 mm² using a leading edge 0.18 micron CMOS/DRAM/APS process. The integrated circuit size and cost can scale somewhat with Moore's law, but is dominated by a CMOS active pixel sensor array 201, so scaling is limited as the sensor pixels approach the diffraction limit.

The ICP 48 includes CMOS logic, a CMOS image sensor, DRAM, and analog circuitry. A very small amount of flash memory or other non-volatile memory is also preferably included for protection against reverse engineering.

Alternatively, the ICP can readily be divided into two integrated circuits: one for the CMOS imaging array, and the other for the remaining circuitry. The cost of this two integrated circuit solution should not be significantly different than the single integrated circuit ICP, as the extra cost of packaging and bond-pad area is somewhat cancelled by the reduced total wafer area requiring the color filter fabrication steps.

The ICP preferably contains the following functions: Function 1.5 megapixel image sensor Analog Signal Processors Image sensor column decoders Image sensor row decoders Analogue to Digital Conversion (ADC) Column ADC's Auto exposure 12 Mbits of DRAM DRAM Address Generator Color interpolator Convolver Color ALU Halftone matrix ROM Digital halftoning Print head interface 8 bit CPU core Program ROM Flash memory Scratchpad SRAM Parallel interface (8 bit) Motor drive transistors (5) Clock PLL JTAG test interface Function Test circuits Busses Bond pads

The CPU, DRAM, Image sensor, ROM, Flash memory, Parallel interface, JTAG interface and ADC can be vendor supplied cores. The ICP is intended to run on 1.5V to minimize power consumption and allow convenient operation from two AA type battery cells.

FIG. 15 illustrates a layout of the ICP 48. The ICP 48 is dominated by the imaging array 201, which consumes around 80% of the integrated circuit area. The imaging array is a CMOS 4 transistor active pixel design with a resolution of 1,500×1,000. The array can be divided into the conventional configuration, with two green pixels, one red pixel, and one blue pixel in each pixel group. There are 750×500 pixel groups in the imaging array.

The latest advances in the field of image sensing and CMOS image sensing in particular can be found in the October, 1997 issue of IEEE Transactions on Electron Devices and, in particular, pages 1689 to 1968. Further, a specific implementation similar to that disclosed in the present application is disclosed in Wong et. al, “CMOS Active Pixel Image Sensors Fabricated Using a 1.8V, 0.25 μm CMOS Technology”, IEDM 1996, page 915

The imaging array uses a 4 transistor active pixel design of a standard configuration. To minimize integrated circuit area and therefore cost, the image sensor pixels should be as small as feasible with the technology available. With a four transistor cell, the typical pixel size scales as 20 times the lithographic feature size. This allows a minimum pixel area of around 3.6 μm×3.6 μm. However, the photosite must be substantially above the diffraction limit of the lens. It is also advantageous to have a square photosite, to maximize the margin over the diffraction limit in both horizontal and vertical directions. In this case, the photosite can be specified as 2.5 μm×2.5 μm. The photosite can be a photogate, pinned photodiode, charge modulation device, or other sensor.

The four transistors are packed as an ‘L’ shape, rather than a rectangular region, to allow both the pixel and the photosite to be square. This reduces the transistor packing density slightly, increasing pixel size. However, the advantage in avoiding the diffraction limit is greater than the small decrease in packing density.

The transistors also have a gate length which is longer than the minimum for the process technology. These have been increased from a drawn length of 0.18 micron to a drawn length of 0.36 micron. This is to improve the transistor matching by making the variations in gate length represent a smaller proportion of the total gate length.

The extra gate length, and the ‘L’ shaped packing, mean that the transistors use more area than the minimum for the technology. Normally, around 8 μm² would be required for rectangular packing. Preferably, 9.75 μm² has been allowed for the transistors.

The total area for each pixel is 16 μm², resulting from a pixel size of 4 μm×4 μm. With a resolution of 1,500×1,000, the area of the imaging array 101 is 6,000 μm×4,000 μm, or 24 mm².

The presence of a color image sensor on the integrated circuit affects the process required in two major ways:

-   -   The CMOS fabrication process should be optimized to minimize         dark current

Color filters are required. These can be fabricated using dyed photosensitive polyimides, resulting in an added process complexity of three spin coatings, three photolithographic steps, three development steps, and three hardbakes.

There are 15,000 analog signal processors (ASPs) 205, one for each of the columns of the sensor. The ASPs amplify the signal, provide a dark current reference, sample and hold the signal, and suppress the fixed pattern noise (FPN).

There are 375 analog to digital converters 206, one for each four columns of the sensor array. These may be delta-sigma or successive approximation type ADC's. A row of low column ADC's are used to reduce the conversion speed required, and the amount of analog signal degradation incurred before the signal is converted to digital. This also eliminates the hot spot (affecting local dark current) and the substrate coupled noise that would occur if a single high speed ADC was used. Each ADC also has two four bit DAC's which trim the offset and scale of the ADC to further reduce FPN variations between columns. These DAC's are controlled by data stored in flash memory during integrated circuit testing.

The column select logic 204 is a 1:1500 decoder which enables the appropriate digital output of the ADCs onto the output bus. As each ADC is shared by four columns, the least significant two bits of the row select control 4 input analog multiplexors.

A row decoder 207 is a 1:1000 decoder which enables the appropriate row of the active pixel sensor array. This selects which of the 1000 rows of the imaging array is connected to analog signal processors. As the rows are always accessed in sequence, the row select logic can be implemented as a shift register.

An auto exposure system 208 adjusts the reference voltage of the ADC 205 in response to the maximum intensity sensed during the previous frame period. Data from the green pixels is passed through a digital peak detector. The peak value of the image frame period before capture (the reference frame) is provided to a digital to analogue converter(DAC), which generates the global reference voltage for the column ADCs. The peak detector is reset at the beginning of the reference frame. The minimum and maximum values of the three RGB color components are also collected for color correction.

The second largest section of the integrated circuit is consumed by a DRAM 210 used to hold the image. To store the 1,500×1,000 image from the sensor without compression, 1.5 Mbytes of DRAM 210 are required. This equals 12 Mbits, or slightly less than 5% of a 256 Mbit DRAM. The DRAM technology assumed is of the 256 Mbit generation implemented using 0.18 μm CMOS.

Using a standard 8F cell, the area taken by the memory array is 3.11 mm². When row decoders, column sensors, redundancy, and other factors are taken into account, the DRAM requires around 4 mm².

This DRAM 210 can be mostly eliminated if analog storage of the image signal can be accurately maintained in the CMOS imaging array for the two seconds required to print the photo. However, digital storage of the image is preferable as it is maintained without degradation, is insensitive to noise, and allows copies of the photo to be printed considerably later.

A DRAM address generator 211 provides the write and read addresses to the DRAM 210. Under normal operation, the write address is determined by the order of the data read from the CMOS image sensor 201. This will typically be a simple raster format. However, the data can be read from the sensor 201 in any order, if matching write addresses to the DRAM are generated. The read order from the DRAM 210 will normally simply match the requirements of a color interpolator and the print head. As the cyan, magenta, and yellow rows of the print head are necessarily offset by a few pixels to allow space for nozzle actuators, the colors are not read from the DRAM simultaneously. However, there is plenty of time to read all of the data from the DRAM many times during the printing process. This capability is used to eliminate the need for FIFOs in the print head interface, thereby saving integrated circuit area. All three RGB image components can be read from the DRAM each time color data is required. This allows a color space converter to provide a more sophisticated conversion than a simple linear RGB to CMY conversion.

Also, to allow two dimensional filtering of the image data without requiring line buffers, data is re-read from the DRAM array.

The address generator may also implement image effects in certain models of camera. For example, passport photos are generated by a manipulation of the read addresses to the DRAM. Also, image framing effects (where the central image is reduced), image warps, and kaleidoscopic effects can all be generated by manipulating the read addresses of the DRAM.

While the address generator 211 may be implemented with substantial complexity if effects are built into the standard integrated circuit, the integrated circuit area required for the address generator is small, as it consists only of address counters and a moderate amount of random logic.

A color interpolator 214 converts the interleaved pattern of red, 2×green, and blue pixels into RGB pixels. It consists of three 8 bit adders and associated registers. The divisions are by either 2 (for green) or 4 (for red and blue) so they can be implemented as fixed shifts in the output connections of the adders.

A convolver 215 is provided as a sharpening filter which applies a small convolution kernel (5×5) to the red, green, and blue planes of the image. The convolution kernel for the green plane is different from that of the red and blue planes, as green has twice as many samples. The sharpening filter has five functions:

-   -   To improve the color interpolation from the linear interpolation         provided by the color interpolator, to a close approximation of         a sinc interpolation.     -   To compensate for the image ‘softening’ which occurs during         digitization.     -   To adjust the image sharpness to match average consumer         preferences, which are typically for the image to be slightly         sharper than reality. As the single use camera is intended as a         consumer product, and not a professional photographic products,         the processing can match the most popular settings, rather than         the most accurate.     -   To suppress the sharpening of high frequency (individual pixel)         noise. The function is similar to the ‘unsharp mask’ process.     -   To antialias Image Warping.

These functions are all combined into a single convolution matrix. As the pixel rate is low (less than 1 Mpixel per second) the total number of multiplies required for the three color channels is 56 million multiplies per second. This can be provided by a single multiplier. Fifty bytes of coefficient ROM are also required.

A color ALU 113 combines the functions of color compensation and color space conversion into the one matrix multiplication, which is applied to every pixel of the frame. As with sharpening, the color correction should match the most popular settings, rather than the most accurate.

A color compensation circuit of the color ALU provides compensation for the lighting of the photo. The vast majority of photographs are substantially improved by a simple color compensation, which independently normalizes the contrast and brightness of the three color components.

A color look-up table (CLUT) 212 is provided for each color component. These are three separate 256×8 SRAMs, requiring a total of 6,144 bits. The CLUTs are used as part of the color correction process. They are also used for color special effects, such as stochastically selected “wild color” effects.

A color space conversion system of the color ALU converts from the RGB color space of the image sensor to the CMY color space of the printer. The simplest conversion is a 1's complement of the RGB data. However, this simple conversion assumes perfect linearity of both color spaces, and perfect dye spectra for both the color filters of the image sensor, and the ink dyes. At the other extreme is a tri-linear interpolation of a sampled three dimensional arbitrary transform table. This can effectively match any non-linearity or differences in either color space. Such a system is usually necessary to obtain good color space conversion when the print engine is a color electrophotographic

However, since the non-linearity of a halftoned ink jet output is very small, a simpler system can be used. A simple matrix multiply can provide excellent results. This requires nine multiplies and six additions per contone pixel. However, since the contone pixel rate is low (less than 1 Mpixel/sec) these operations can share a single multiplier and adder. The multiplier and adder are used in a color ALU which is shared with the color compensation function.

Digital halftoning can be performed as a dispersed dot ordered dither using a stochastic optimized dither cell. A halftone matrix ROM 216 is provided for storing dither cell coefficients. A dither cell size of 32×32 is adequate to ensure that the cell repeat cycle is not visible. The three colors-cyan, magenta, and yellow-are all dithered using the same cell, to ensure maximum co-positioning of the ink dots. This minimizes ‘muddying’ of the mid-tones which results from bleed of dyes from one dot to adjacent dots while still wet. The total ROM size required is 1 KByte, as the one ROM is shared by the halftoning units for each of the three colors.

The digital halftoning used is dispersed dot ordered dither with stochastic optimized dither matrix. While dithering does not produce an image quite as ‘sharp’ as error diffusion, it does produce a more accurate image with fewer artifacts. The image sharpening produced by error diffusion is artificial, and less controllable and accurate than ‘unsharp mask’ filtering performed in the contone domain. The high print resolution (1,600 dpi×1,600 dpi) results in excellent quality when using a well formed stochastic dither matrix.

Digital halftoning is performed by a digital halftoning unit 217 using a simple comparison between the contone information from the DRAM 210 and the contents of the dither matrix 216. During the halftone process, the resolution of the image is changed from the 250 dpi of the captured contone image to the 1,600 dpi of the printed image. Each contone pixel is converted to an average of 40.96 halftone dots.

The ICP incorporates a 16 bit microcontroller CPU core 219 to run the miscellaneous camera functions, such as reading the buttons, controlling the motor and solenoids, setting up the hardware, and authenticating the refill station. The processing power required by the CPU is very modest, and a wide variety of processor cores can be used. As the entire CPU program is run from a small ROM 220[.], program compatibility between camera versions is not important, as no external programs are run. A 2 Mbit (256 Kbyte) program and data ROM 220 is included on integrated circuit. Most of this ROM space is allocated to data for outline graphics and fonts for specialty cameras. The program requirements are minor. The single most complex task is the encrypted authentication of the refill station. The ROM requires a single transistor per bit.

A Flash memory 221 may be used to store a 128 bit authentication code. This provides higher security than storage of the authentication code in ROM, as reverse engineering can be made essentially impossible. The Flash memory is completely covered by third level metal, making the data impossible to extract using scanning probe microscopes or electron beams. The authentication code is stored in the integrated circuit when manufactured. At least two other Flash bits are required for the authentication process: a bit which locks out reprogramming of the authentication code, and a bit which indicates that the camera has been refilled by an authenticated refill station. The flash memory can also be used to store FPN correction data for the imaging array. Additionally, a phase locked loop rescaling parameter is stored for scaling the clocking cycle to an appropriate correct time. The clock frequency does not require crystal accuracy since no date functions are provided. To eliminate the cost of a crystal, an on integrated circuit oscillator with a phase locked loop 224 is used. As the frequency of an on-integrated circuit oscillator is highly variable from integrated circuit to integrated circuit, the frequency ratio of the oscillator to the PLL is digitally trimmed during initial testing. The value is stored in Flash memory 221. This allows the clock PLL to control the ink-jet heater pulse width with sufficient accuracy.

A scratchpad SRAM is a small static RAM 222 with a 6T cell. The scratchpad provided temporary memory for the 16 bit CPU. 1024 bytes is adequate.

A print head interface 223 formats the data correctly for the print head. The print head interface also provides all of the timing signals required by the print head. These timing signals may vary depending upon temperature, the number of dots printed simultaneously, the print medium in the print roll, and the dye density of the ink in the print roll.

The following is a table of external connections to the print head interface: Connection Function Pins DataBits[0-7] Independent serial data to the eight segments 8 of the print head BitClock Main data clock for the print head 1 ColorEnable[0-2] Independent enable signals for the CMY 3 actuators, allowing different pulse times for each color. BankEnable[0-1] Allows either simultaneous or interleaved 2 actuation of two banks of nozzles. This allows two different print speed/power consumption tradeoffs NozzleSelect[0-4] Selects one of 32 banks of nozzles for 5 simultaneous actuation ParallelXferClock Loads the parallel transfer register with the 1 data from the shift registers Total 20

The print head utilized is composed of eight identical segments, each 1.25 cm long. There is no connection between the segments on the print head integrated circuit. Any connections required are made in the external TAB bonding film, which is double sided. The division into eight identical segments is to simplify lithography using wafer steppers. The segment width of 1.25 cm fits easily into a stepper field. As the print head integrated circuit is long and narrow (10 cm×0.3 mm), the stepper field contains a single segment of 32 print head integrated circuits. The stepper field is therefore 1.25 cm×1.6 cm. An average of four complete print heads are patterned in each wafer step.

A single BitClock output line connects to all 8 segments on the print head. The 8 DataBits lines lead one to each segment, and are clocked into the 8 segments on the print head simultaneously (on a BitClock pulse). For example, dot 0 is transferred to segment₀, dot 750 is transferred to segment₁, dot 1500 to segment₂ etc simultaneously.

The ParallelXferClock is connected to each of the 8 segments on the print head, so that on a single pulse, all segments transfer their bits at the same time.

The NozzleSelect, BankEnable and ColorEnable lines are connected to each of the 8 segments, allowing the print head interface to independently control the duration of the cyan, magenta, and yellow nozzle energizing pulses. Registers in the Print Head Interface allow the accurate specification of the pulse duration between 0 and 6 ms, with a typical duration of 2 ms to 3 ms.

A parallel interface 125 connects the ICP to individual static electrical signals. The CPU is able to control each of these connections as memory mapped I/O via a low speed bus.

The following is a table of connections to the parallel interface: Connection Direction Pins Paper transport stepper motor Output 4 Capping solenoid Output 1 Copy LED Output 1 Photo button Input 1 Copy button Input 1 Total 8

Seven high current drive transistors eg. 227 are required. Four are for the four phases of the main stepper motor, two are for the guillotine motor, and the remaining transistor is to drive the capping solenoid. These transistors are allocated 20,000 square microns (600,000 F) each. As the transistors are driving highly inductive loads, they must either be turned off slowly, or be provided with a high level of back EMF protection. If adequate back EMF protection cannot be provided using the integrated circuit process chosen, then external discrete transistors should be used. The transistors are never driven at the same time as the image sensor is used. This is to avoid voltage fluctuations and hot spots affecting the image quality. Further, the transistors are located as far away from the sensor as possible.

A standard JTAG (Joint Test Action Group) interface 228 is included in the ICP for testing purposes and for interrogation by the refill station. Due to the complexity of the integrated circuit, a variety of testing techniques are required, including BIST (Built In Self Test) and functional block isolation. An overhead of 10% in integrated circuit area is assumed for integrated circuit testing circuitry for the random logic portions. The overhead for the large arrays the image sensor and the DRAM is smaller.

The JTAG interface is also used for authentication of the refill station. This is included to ensure that the cameras are only refilled with quality paper and ink at a properly constructed refill station, thus preventing inferior quality refills from occurring. The camera must authenticate the refill station, rather than vice versa. The secure protocol is communicated to the refill station during the automated test procedure. Contact is made to four gold plated spots on the ICP/print head TAB by the refill station as the new ink is injected into the print head.

FIG. 16 illustrates a rear view of the next step in the construction process whilst FIG. 17 illustrates a front view.

Turning now to FIG. 16, the assembly of the camera system proceeds via first assembling the ink supply mechanism 40. The flex PCB is interconnected with batteries 84 only one of which is shown, which are inserted in the middle portion of a print roll 85 which is wrapped around a plastic former 86. An end cap 89 is provided at the other end of the print roll 85 so as to fasten the print roll and batteries firmly to the ink supply mechanism.

The solenoid coil is interconnected (not shown) to interconnects 97, 98 (FIG. 8) which include leaf spring ends for interconnection with electrical contacts on the Flex PCB so as to provide for electrical control of the solenoid.

Turning now to FIGS. 17-19 the next step in the construction process is the insertion of the relevant gear trains into the side of the camera chassis. FIG. 17 illustrates a front view, FIG. 18 illustrates a rear view and FIG. 19 also illustrates a rear view. The first gear train comprising gear wheels 22, 23 is utilised for driving the guillotine blade with the gear wheel 23 engaging the gear wheel 65 of FIG. 8. The second gear train comprising gear wheels 24, 25 and 26 engage one end of the print roller 61 of FIG. 8. As best indicated in FIG. 18, the gear wheels mate with corresponding pins on the surface of the chassis with the gear wheel 26 being snap fitted into corresponding mating hole 27.

Next, as illustrated in FIG. 20, the assembled platen unit 60 is then inserted between the print roll 85 and aluminium cutting blade 43.

Turning now to FIG. 21, by way of illumination, there is illustrated the electrically interactive components of the camera system. As noted previously, the components are based around a Flex PCB board and include a TAB film 58 which interconnects the printhead 102 with the image sensor and processing integrated circuit 48. Power is supplied by two AA type batteries 83, 84 and a paper drive stepper motor 16 is provided in addition to a rotary guillotine motor 17.

An optical element 31 is provided for snapping into a top portion of the chassis 12. The optical element 31 includes portions defining an optical view finder 32, 33 which are slotted into mating portions 35, 36 in view finder channel 37. Also provided in the optical element 31 is a lensing system 38 for magnification of the prints left number in addition to an optical pipe element 39 for piping light from the LED 5 for external display.

Turning next to FIG. 22, the assembled unit 90 is then inserted into a front outer case 91 which includes button 4 for activation of printouts.

Turning now to FIG. 23, next, the unit 90 is provided with a snap-on back cover 93 which includes a slot 6 and copy print button 7. A wrapper label containing instructions and advertising (not shown) is then wrapped around the outer surface of the camera system and pinch clamped to the cover by means of clamp strip 96 which can comprise a flexible plastic or rubber strip.

Subsequently, the preferred embodiment is ready for use as a one time use camera system that provides for instant output images on demand. It will be evident that the preferred embodiment further provides for a refillable camera system. A used camera can be collected and its outer plastic cases removed and recycled. A new paper roll and batteries can be added and the ink cartridge refilled. A series of automatic test routines can then be carried out to ensure that the printer is properly operational. Further, in order to ensure only authorised refills are conducted so as to enhance quality, routines in the on-integrated circuit program ROM can be executed such that the camera authenticates the refilling station using a secure protocol. Upon authentication, the camera can reset an internal paper count and an external case can be fitted on the camera system with a new outer label. Subsequent packing and shipping can then take place.

It will be further readily evident to those skilled in the art that the program ROM can be modified so as to allow for a variety of digital processing routines. In addition to the digitally enhanced photographs optimised for mainstream consumer preferences, various other models can readily be provided through mere re-programming of the program ROM. For example, a sepia classic old fashion style output can be provided through a remapping of the colour mapping function. A further alternative is to provide for black and white outputs again through a suitable colour remapping algorithm. Minimum colour can also be provided to add a touch of colour to black and white prints to produce the effect that was traditionally used to colourize black and white photos. Further, passport photo output can be provided through suitable address remappings within the address generators. Further, edge filters can be utilised as is known in the field of image processing to produce sketched art styles. Further, classic wedding borders and designs can be placed around an output image in addition to the provision of relevant clip arts. For example, a wedding style camera might be provided. Further, a panoramic mode can be provided so as to output the well known panoramic format of images. Further, a postcard style output can be provided through the printing of postcards including postage on the back of a print roll surface. Further, cliparts can be provided for special events such as Halloween, Christmas etc. Further, kaleidoscopic effects can be provided through address remappings and wild colour effects can be provided through remapping of the colour lookup table. Many other forms of special event cameras can be provided for example, cameras dedicated to the Olympics, movie tie-ins, advertising and other special events.

The operational mode of the camera can be programmed so that upon the depressing of the take photo a first image is sampled by the sensor array to determine irrelevant parameters. Next a second image is again captured which is utilised for the output The captured image is then manipulated in accordance with any special requirements before being initially output on the paper roll. The LED light is then activated for a predetermined time during which the DRAM is refreshed so as to retain the image. If the print copy button is depressed during this predetermined time interval, a further copy of the photo is output After the predetermined time interval where no use of the camera has occurred, the onboard CPU shuts down all power to the camera system until such time as the take button is again activated. In this way, substantial power savings can be realized.

Ink Jet Technologies

The embodiments of the invention use an ink jet printer type device. Of course many different devices could be used. However presently popular ink jet printing technologies are unlikely to be suitable.

The most significant problem with thermal inkjet is power consumption. This is approximately 100 times that required for high speed, and stems from the energy-inefficient means of drop ejection. This involves the rapid boiling of water to produce a vapor bubble which expels the ink. Water has a very high heat capacity, and must be superheated in thermal inkjet applications. This leads to an efficiency of around 0.02%, from electricity input to drop momentum (and increased surface area) out.

The most significant problem with piezoelectric inkjet is size and cost. Piezoelectric crystals have a very small deflection at reasonable drive voltages, and therefore require a large area for each nozzle. Also, each piezoelectric actuator must be connected to its drive circuit on a separate substrate. This is not a significant problem at the current limit of around 300 nozzles per print head, but is a major impediment to the fabrication of pagewide print heads with 19,200 nozzles.

Ideally, the inkjet technologies used meet the stringent requirements of in-camera digital color printing and other high quality, high speed, low cost printing applications. To meet the requirements of digital photography, new inkjet technologies have been created. The target features include:

-   -   low power (less than 10 Watts)     -   high resolution capability (1,600 dpi or more)     -   photographic quality output     -   low manufacturing cost     -   small size (pagewidth times minimum cross section)     -   high speed (<2 seconds per page).

All of these features can be met or exceeded by the inkjet systems described below with differing levels of difficulty. 45 different inkjet technologies have been developed by the Assignee to give a wide range of choices for high volume manufacture. These technologies form part of separate applications assigned to the present Assignee as set out in the table below.

The inkjet designs shown here are suitable for a wide range of digital printing systems, from battery powered one-time use digital cameras, through to desktop and network printers, and through to commercial printing systems

For ease of manufacture using standard process equipment, the print head is designed to be a monolithic 0.5 micron CMOS integrated circuit with MEMS post processing. For color photographic applications, the print head is 100 mm long, with a width which depends upon the inkjet type. The smallest print head designed is IJ38, which is 0.35 mm wide, giving a integrated circuit area of 35 square mm. The print heads each contain 19,200 nozzles plus data and control circuitry.

Ink is supplied to the back of the print head by injection molded plastic ink channels. The molding requires 50 micron features, which can be created using a lithographically micromachined insert in a standard injection molding tool. Ink flows through holes etched through the wafer to the nozzle chambers fabricated on the front surface of the wafer. The print head is connected to the camera circuitry by tape automated bonding.

Cross-Referenced Applications

The following table is a guide to cross-referenced patent applications filed concurrently herewith and discussed hereinafter with the reference being utilized in subsequent tables when referring to a particular case: Docket No. Reference Title IJ01US IJ01 Radiant Plunger Ink Jet Printer IJ02US IJ02 Electrostatic Ink Jet Printer IJ03US IJ03 Planar Thermoelastic Bend Actuator Ink Jet IJ04US IJ04 Stacked Electrostatic Ink Jet Printer IJ05US IJ05 Reverse Spring Lever Ink Jet Printer IJ06US IJ06 Paddle Type Ink Jet Printer IJ07US IJ07 Permanent Magnet Electromagnetic Ink Jet Printer IJ08US IJ08 Planar Swing Grill Electromagnetic Ink Jet Printer IJ09US IJ09 Pump Action Refill Ink Jet Printer IJ10US IJ10 Pulsed Magnetic Field Ink Jet Printer IJ11US IJ11 Two Plate Reverse Firing Electromagnetic Ink Jet Printer IJ12US IJ12 Linear Stepper Actuator Ink Jet Printer IJ13US IJ13 Gear Driven Shutter Ink Jet Printer IJ14US IJ14 Tapered Magnetic Pole Electromagnetic Ink Jet Printer IJ15US IJ15 Linear Spring Electromagnetic Grill Ink Jet Printer IJ16US IJ16 Lorenz Diaphragm Electromagnetic Ink Jet Printer IJ17US IJ17 PTFE Surface Shooting Shuttered Oscillating Pressure Ink Jet Printer IJ18US IJ18 Buckle Grip Oscillating Pressure Ink Jet Printer IJ19US IJ19 Shutter Based Ink Jet Printer IJ20US IJ20 Curling Calyx Thermoelastic Ink Jet Printer IJ21US IJ21 Thermal Actuated Ink Jet Printer IJ22US IJ22 Iris Motion Ink Jet Printer IJ23US IJ23 Direct Firing Thermal Bend Actuator Ink Jet Printer IJ24US IJ24 Conductive PTFE Ben Activator Vented Ink Jet Printer IJ25US IJ25 Magnetostrictive Ink Jet Printer IJ26US IJ26 Shape Memory Alloy Ink Jet Printer IJ27US IJ27 Buckle Plate Ink Jet Printer IJ28US IJ28 Thermal Elastic Rotary Impeller Ink Jet Printer IJ29US IJ29 Thermoelastic Bend Actuator Ink Jet Printer IJ30US IJ30 Thermoelastic Bend Actuator Using PTFE and Corrugated Copper Ink Jet Printer IJ31US IJ31 Bend Actuator Direct Ink Supply Ink Jet Printer IJ32US IJ32 A High Young's Modulus Thermoelastic Ink Jet Printer IJ33US IJ33 Thermally actuated slotted chamber wall ink jet printer IJ34US IJ34 Ink Jet Printer having a thermal actuator comprising an external coiled spring IJ35US IJ35 Trough Container Ink Jet Printer IJ36US IJ36 Dual Chamber Single Vertical Actuator Ink Jet IJ37US IJ37 Dual Nozzle Single Horizontal Fulcrum Actuator Ink Jet IJ38US IJ38 Dual Nozzle Single Horizontal Actuator Ink Jet IJ39US IJ39 A single bend actuator cupped paddle ink jet printing device IJ40US IJ40 A thermally actuated ink jet printer having a series of thermal actuator units IJ41US IJ41 A thermally actuated ink jet printer including a tapered heater element IJ42US IJ42 Radial Back-Curling Thermoelastic Ink Jet IJ43US IJ43 Inverted Radial Back-Curling Thermoelastic Ink Jet IJ44US IJ44 Surface bend actuator vented ink supply ink jet printer IJ45US IJ45 Coil Acutuated Magnetic Plate Ink Jet Printer Tables of Drop-On-Demand Inkjets

Eleven important characteristics of the fundamental operation of individual inkjet nozzles have been identified. These characteristics are largely orthogonal, and so can be elucidated as an eleven dimensional matrix. Most of the eleven axes of this matrix include entries developed by the present assignee.

The following tables form the axes of an eleven dimensional table of inkjet types.

-   -   Actuator mechanism (18 types)     -   Basic operation mode (7 types)     -   Auxiliary mechanism (8 types)     -   Actuator amplification or modification method (17 types)     -   Actuator motion (19 types)     -   Nozzle refill method (4 types)     -   Method of restricting back-flow through inlet (10 types)     -   Nozzle clearing method (9 types)     -   Nozzle plate construction (9 types)     -   Drop ejection direction (5 types)     -   Ink type (7 types)

The complete eleven dimensional table represented by these axes contains 36.9 billion possible configurations of inkjet nozzle. While not all of the possible combinations result in a viable inkjet technology, many million configurations are viable. It is clearly impractical to elucidate all of the possible configurations. Instead, certain inkjet types have been investigated in detail. These are designated IJ01 to IJ45 above.

Other inkjet configurations can readily be derived from these 45 examples by substituting alternative configurations along one or more of the 11 axes. Most of the IJ01 to U45 examples can be made into inkjet print heads with characteristics superior to any currently available inkjet technology.

Where there are prior art examples known to the inventor, one or more of these examples are listed in the examples column of the tables below. The IJ01 to IJ45 series are also listed in the examples column. In some cases, a printer may be listed more than once in a table, where it shares characteristics with more than one entry.

Suitable applications include: Home printers, Office network printers, Short run digital printers, Commercial print systems, Fabric printers, Pocket printers, Internet WWW printers, Video printers, Medical imaging, Wide format printers, Notebook PC printers, Fax machines, Industrial printing systems, Photocopiers, Photographic minilabs etc.

The information associated with the aforementioned 11 dimensional matrix are set out in the following tables. Actuator mechanism (applied only to selected ink drops) Actuator Mechanism Description Advantages Disadvantages Examples Thermal bubble An electrothermal heater heats the ink to Large force generated High power Canon Bubblejet 1979 above boiling point, transferring Simple construction Ink carrier limited to water Endo et al GB patent significant heat to the aqueous ink. A No moving parts Low efficiency 2,007,162 bubble nucleates and quickly forms, Fast operation High temperatures required Xerox heater-in-pit 1990 expelling the ink. Small integrated circuit area High mechanical stress Hawkins et al U.S. Pat. No. The efficiency of the process is low, with required for actuator Unusual materials required 4,899,181 typically less than 0.05% of the electrical Large drive transistors Hewlett-Packard TIJ 1982 energy being transformed into kinetic energy of the Cavitation causes actuator failure Vaught et al U.S. Pat. No. drop. Kogation reduces bubble formation 4,490,728 Large print heads are difficult to fabricate Piezoelectric A piezoelectric crystal such as lead Low power consumption Very large area required for actuator Kyser et al U.S. Pat. No. 3,946,398 lanthanum zirconate (PZT) is electrically Many ink types can be used Difficult to integrate with electronics Zoltan U.S. Pat. No. 3,683,212 activated, and either expands, shears, or Fast operation High voltage drive transistors required 1973 Stemme U.S. Pat. No. bends to apply pressure to the ink, High efficiency Full pagewidth print heads impractical due to 3,747,120 ejecting drops. actuator size Epson Stylus Requires electrical poling in high field Tektronix strengths during manufacture IJ04 Electro-strictive An electric field is used to activate Low power consumption Low maximum strain (approx. 0.01%) Seiko Epson, Usui et all JP electrostriction in relaxor materials such Many ink types can be used Large area required for actuator due to low 253401/96 as lead lanthanum zirconate titanate Low thermal expansion strain IJ04 (PLZT) or lead magnesium niobate Electric field strength required Response speed is marginal (˜10 μs) (PMN). (approx. 3.5 V/μm) can be High voltage drive transistors required generated without difficulty Full pagewidth print heads impractical due to Does not require actuator size electrical poling Ferroelectric An electric field is used to induce a Low power consumption Difficult to integrate with electronics IJ04 phase transition between the Many ink types can be used Unusual materials such as PLZSnT are antiferroelectric (AFE) and ferroelectric Fast operation (<1 μs) required (FE) phase. Perovskite materials such as Relatively high longitudinal strain Actuators require a large area tin modified lead lanthanum zirconate High efficiency titanate (PLZSnT) exhibit large strains of Electric field strength of around 3 V/μm up to 1% associated with the AFE to FE can be readily provided phase transition. Electrostatic plates Conductive plates are separated by a Low power consumption Difficult to operate electrostatic devices in an IJ02, IJ04 compressible or fluid dielectric (usually Many ink types can be used aqueous environment air). Upon application of a voltage, the Fast operation The electrostatic actuator will normally need plates attract each other and displace ink, to be separated from the ink causing drop ejection. The conductive Very large area required to achieve high plates may be in a comb or honeycomb forces structure, or stacked to increase the High voltage drive transistors may surface area and therefore the force. be required Full pagewidth print heads are not competitive due to actuator size Electrostatic pull A strong electric field is applied to the Low current consumption High voltage required 1989 Saito et al, U.S. Pat. No. on ink ink, whereupon electrostatic attraction Low temperature May be damaged by sparks due to air 4,799,068 accelerates the ink towards the print breakdown 1989 Miura et al, U.S. Pat. No. medium. Required field strength increases as the drop 4,810,954 size decreases Tone-jet High voltage drive transistors required Electrostatic field attracts dust Permanent magnet An electromagnet directly attracts a Low power consumption Complex fabrication IJ07, IJ10 electro-magnetic permanent magnet, displacing ink and Many ink types can be used Permanent magnetic material such as causing drop ejection. Rare earth Fast operation Neodymium Iron Boron (NdFeB) required. magnets with a field strength around 1 High efficiency High local currents required Tesla can be used. Examples are: Easy extension from single Copper metalization should be used for long Samarium Cobalt (SaCo) and magnetic nozzles to pagewidth print heads electromigration lifetime and low resistivity materials in the neodymium iron boron Pigmented inks are usually infeasible family (NdFeB, NdDyFeBNb, Operating temperature limited to the Curie NdDyFeB, etc) temperature (around 540 K) Soft magnetic core A solenoid induced a magnetic field in a Low power consumption Complex fabrication IJ01, IJ05, IJ08, IJ10 electro-magnetic soft magnetic core or yoke fabricated Many ink types can be used Materials not usually present in a CMOS fab IJ12, IJ14, IJ15, IJ17 from a ferrous material such as Fast operation such as NiFe, CoNiFe, or CoFe are required electroplated iron alloys such as CoNiFe High efficiency High local currents required [1], CoFe, or NiFe alloys. Typically, the Easy extension from single Copper metalization should be used for long soft magnetic material is in two parts, nozzles to pagewidth print heads electromigration lifetime and low resistivity which are normally held apart by a Electroplating is required spring. When the solenoid is actuated, High saturation flux density is required (2.0-2.1 the two parts attract, displacing the ink. T is achievable with CoNiFe [1]) Magnetic The Lorenz force acting on a current Low power consumption Force acts as a twisting motion IJ06, IJ11, IJ13, IJ16 Lorenz force carrying wire in a magnetic field is Many ink types can be used Typically, only a quarter of the solenoid utilized. Fast operation length provides force in a useful direction This allows the magnetic field to be High efficiency High local currents required supplied externally to the print head, for Easy extension from single Copper metalization should be used for long example with rare earth permanent nozzles to pagewidth print heads electromigration lifetime and low resistivity magnets. Pigmented inks are usually infeasible Only the current carrying wire need be fabricated on the print-head, simplifying materials requirements. Magneto-striction The actuator uses the giant Many ink types can be used Force acts as a twisting motion Fischenbeck, U.S. Pat. No. magnetostrictive effect of materials such Fast operation Unusual materials such as Terfenol-D are 4,032,929 as Terfenol-D (an alloy of terbium, Easy extension from single required IJ25 dysprosium and iron developed at the nozzles to pagewidth print heads High local currents required Naval Ordnance Laboratory, hence Ter- High force is available Copper metalization should be used for long Fe-NOL). For best efficiency, the electromigration lifetime and low resistivity actuator should be pre-stressed to Pre-stressing may be required approx. 8 MPa. Surface tension Ink under positive pressure is held in a Low power consumption Requires supplementary force to effect drop Silverbrook, EP 0771 658 reduction nozzle by surface tension. The surface Simple construction separation A2 and related patent tension of the ink is reduced below the No unusual materials required in Requires special ink surfactants applications bubble threshold, causing the ink to fabrication Speed may be limited by surfactant properties egress from the nozzle. High efficiency Easy extension from single nozzles to pagewidth print heads Viscosity reduction The ink viscosity is locally reduced to Simple construction Requires supplementary force to effect drop Silverbrook, EP 0771 658 select which drops are to be ejected. A No unusual materials required in separation A2 and related patent viscosity reduction can be achieved fabrication Requires special ink viscosity properties applications electrothermally with most inks, but Easy extension from single High speed is difficult to achieve special inks can be engineered for a nozzles to pagewidth print heads Requires oscillating ink pressure 100:1 viscosity reduction. A high temperature difference (typically 80 degrees) is required Acoustic An acoustic wave is generated and Can operate without a nozzle Complex drive circuitry 1993 Hadimioglu et al, focussed upon the drop ejection region. plate Complex fabrication EUP 550,192 Low efficiency 1993 Elrod et al, EUP Poor control of drop position 572,220 Poor control of drop volume Thermoelastic bend An actuator which relies upon Low power consumption Efficient aqueous operation requires a thermal IJ03, IJ09, IJ17, IJ18 actuator differential thermal expansion upon Many ink types can be used insulator on the hot side IJ19, IJ20, IJ21, IJ22 Joule heating is used. Simple planar fabrication Corrosion prevention can be difficult IJ23, IJ24, IJ27, IJ28 Small integrated circuit area Pigmented inks may be infeasible, as pigment IJ29, IJ30, IJ31, IJ32 required for each actuator particles may jam the bend actuator IJ33, IJ34, IJ35, IJ36 Fast operation IJ37, IJ38 ,IJ39, IJ40 High efficiency IJ41 CMOS compatible voltages and currents Standard MEMS processes can be used Easy extension from single nozzles to pagewidth print heads High CTE A material with a very high coefficient of High force can be generated Requires special material (e.g. PTFE) IJ09, IJ17, IJ18, IJ20 thermoelastic thermal expansion (CTE) such as PTFE is a candidate for low Requires a PTFE deposition process, which is IJ21, IJ22, IJ23, IJ24 actuator polytetrafluoroethylene (PTFE) is used. dielectric constant insulation in not yet standard in ULSI fabs IJ27, IJ28, IJ29, IJ30 As high CTE materials are usually non- ULSI PTFE deposition cannot be followed with high IJ31, IJ42, IJ43, IJ44 conductive, a heater fabricated from a Very low power consumption temperature (above 350° C.) processing conductive material is incorporated. A 50 μm Many ink types can be used Pigmented inks may be infeasible, as pigment long PTFE bend actuator with Simple planar fabrication particles may jam the bend actuator polysilicon heater and 15 mW power Small integrated circuit area input can provide 180 μN force and 10 μm required for each actuator deflection. Actuator motions include: Fast operation Bend High efficiency Push CMOS compatible voltages and Buckle currents Rotate Easy extension from single nozzles to pagewidth print heads Conductive A polymer with a high coefficient of High force can be generated Requires special materials development (High IJ24 polymer thermal expansion (such as PTFE) is Very low power consumption CTE conductive polymer) thermoelastic doped with conducting substances to Many ink types can be used Requires a PTFE deposition process, which is actuator increase its conductivity to about 3 Simple planar fabrication not yet standard in ULSI fabs orders of magnitude below that of Small integrated circuit area PTFE deposition cannot be followed with high copper. The conducting polymer expands required for each actuator temperature (above 350° C.) processing when resistively heated. Fast operation Evaporation and CVD deposition techniques Examples of conducting dopants include: High efficiency cannot be used Carbon nanotubes CMOS compatible voltages and Pigmented inks may be infeasible, as pigment Metal fibers currents particles may jam the bend actuator Conductive polymers such as doped Easy extension from single polythiophene nozzles to pagewidth print heads Carbon granules Shape memory A shape memory alloy such as TiNi (also High force is available (stresses of Fatigue limits maximum number of cycles IJ26 alloy known as Nitinol - Nickel Titanium alloy hundreds of MPa) Low strain (1%) is required to extend fatigue developed at the Naval Ordnance Large strain is available (more resistance Laboratory) is thermally switched than 3%) Cycle rate limited by heat removal between its weak martensitic state and its High corrosion resistance Requires unusual materials (TiNi) high stiffness austenic state. The shape of Simple construction The latent heat of transformation must be the actuator in its martensitic state is Easy extension from single provided deformed relative to the austenic shape. nozzles to pagewidth print heads High current operation The shape change causes ejection of a Low voltage operation Requires pre-stressing to distort the drop. martensitic state Linear Magnetic Linear magnetic actuators include the Linear Magnetic actuators can be Requires unusual semiconductor materials IJ12 Actuator Linear Induction Actuator (LIA), Linear constructed with high thrust, long such as soft magnetic alloys (e.g. CoNiFe [1]) Permanent Magnet Synchronous travel, and high efficiency using Some varieties also require permanent Actuator (LPMSA), Linear Reluctance planar semiconductor fabrication magnetic materials such as Neodymium iron Synchronous Actuator (LRSA), Linear techniques boron (NdFeB) Switched Reluctance Actuator (LSRA), Long actuator travel is available Requires complex multi-phase drive circuitry and the Linear Stepper Actuator (LSA). Medium force is available High current operation Low voltage operation

Basic operation mode Operational mode Description Advantages Disadvantages Examples Actuator directly pushes ink This is the simplest mode of operation: Simple operation Drop repetition rate is usually limited to less Thermal inkjet the actuator directly supplies sufficient No external fields required than 10 KHz. However, this is not Piezoelectric inkjet kinetic energy to expel the drop. The Satellite drops can be avoided if fundamental to the method, but is related to IJ01, IJ02, IJ03, IJ04 drop must have a sufficient velocity to drop velocity is less than 4 m/s the refill method normally used IJ05, IJ06, IJ07, IJ09 overcome the surface tension. Can be efficient, depending upon All of the drop kinetic energy must be IJ11, IJ12, IJ14, IJ16 the actuator used provided by the actuator IJ20, IJ22, IJ23, IJ24 Satellite drops usually form if drop velocity is greater than IJ25, IJ26, IJ27, IJ28 4.5 m/s IJ29, IJ30, IJ31, IJ32 IJ33, IJ34, IJ35, IJ36 IJ37, IJ38, IJ39, IJ40 IJ41, IJ42, IJ43, IJ44 Proximity The drops to be printed are selected by Very simple print head fabrication Requires close proximity between the print Silverbrook, EP 0771 658 some manner (e.g. thermally induced can be used head and the print media or transfer roller A2 and related patent surface tension reduction of pressurized The drop selection means does May require two print heads printing alternate applications ink). Selected drops are separated from not need to provide the energy rows of the image the ink in the nozzle by contact with the required to separate the drop from Monolithic color print heads are difficult print medium or a transfer roller. the nozzle Electrostatic pull The drops to be printed are selected by Very simple print head fabrication Requires very high electrostatic field Silverbrook, EP 0771 658 on ink some manner (e.g. thermally induced can be used Electrostatic field for small nozzle sizes is A2 and related patent surface tension reduction of pressurized The drop selection means does above air breakdown applications ink). Selected drops are separated from not need to provide the energy Electrostatic field may attract dust Tone-Jet the ink in the nozzle by a strong electric required to separate the drop from field. the nozzle Magnetic pull on The drops to be printed are selected by Very simple print head fabrication Requires magnetic ink Silverbrook, EP 0771 658 ink some manner (e.g. thermally induced can be used Ink colors other than black are difficult A2 and related patent applications surface tension reduction of pressurized The drop selection means does Requires very high magnetic fields ink). Selected drops are separated from not need to provide the energy the ink in the nozzle by a strong required to separate the drop from magnetic field acting on the magnetic the nozzle ink. Shutter The actuator moves a shutter to block ink High speed (>50 KHz) operation Moving parts are required IJ13, IJ17, IJ21 flow to the nozzle. The ink pressure is can be achieved due to reduced Requires ink pressure modulator pulsed at a multiple of the drop ejection refill time Friction and wear must be considered frequency. Drop timing can be very accurate Stiction is possible The actuator energy can be very low Shuttered grill The actuator moves a shutter to block ink Actuators with small travel can be used Moving parts are required IJ08, IJ15, IJ18, IJ19 flow through a grill to the nozzle. The Actuators with small force can be used Requires ink pressure modulator shutter movement need only be equal to High speed (>50 KHz) operation Friction and wear must be considered the width of the grill holes. can be achieved Stiction is possible Pulsed magnetic A pulsed magnetic field attracts an ‘ink Extremely low energy operation Requires an external pulsed magnetic field IJ10 pull on ink pusher pusher’ at the drop ejection frequency. is possible Requires special materials for both the An actuator controls a catch, which No heat dissipation problems actuator and the ink pusher prevents the ink pusher from moving Complex construction when a drop is not to be ejected.

Auxiliary mechanism (applied to all nozzles) Auxiliary Mechanism Description Advantages Disadvantages Examples None The actuator directly fires the ink drop, Simplicity of construction Drop ejection energy must be supplied by Most inkjets, including and there is no external field or other Simplicity of operation individual nozzle actuator piezoelectric and thermal mechanism required. Small physical size bubble. IJ01-IJ07, IJ09, IJ11 IJ12, IJ14, IJ20, IJ22 IJ23-IJ45 Oscillating ink The ink pressure oscillates, providing Oscillating ink pressure can Requires external ink pressure oscillator Silverbrook, EP 0771 658 pressure much of the drop ejection energy. The provide a refill pulse, allowing Ink pressure phase and amplitude must be A2 and related patent (including acoustic stimulation) actuator selects which drops are to be higher operating speed carefully controlled applications fired by selectively blocking or enabling The actuators may operate with Acoustic reflections in the ink chamber must IJ08, IJ13, IJ15, IJ17 nozzles. The ink pressure oscillation may much lower energy be designed for IJ18, IJ19, IJ21 be achieved by vibrating the print head, Acoustic lenses can be used to or preferably by an actuator in the ink focus the sound on the nozzles supply. Media proximity The print head is placed in close Low power Precision assembly required Silverbrook, EP 0771 658 proximity to the print medium. Selected High accuracy Paper fibers may cause problems A2 and related patent drops protrude from the print head Simple print head construction Cannot print on rough substrates applications further than unselected drops, and contact the print medium. The drop soaks into the medium fast enough to cause drop separation. Transfer roller Drops are printed to a transfer roller High accuracy Bulky Silverbrook, EP 0771 658 instead of straight to the print medium. A Wide range of print substrates can Expensive A2 and related patent transfer roller can also be used for be used Complex construction applications proximity drop separation. Ink can be dried on the transfer Tektronix hot melt roller piezoelectric inkjet Any of the IJ series Electrostatic An electric field is used to accelerate Low power Field strength required for separation of small Silverbrook, EP 0771 658 selected drops towards the print medium. Simple print head construction drops is near or above air breakdown A2 and related patent applications Tone-Jet Direct magnetic A magnetic field is used to accelerate Low power Requires magnetic ink Silverbrook, EP 0771 658 field selected drops of magnetic ink towards Simple print head construction Requires strong magnetic field A2 and related patent the print medium. applications Cross magnetic The print head is placed in a constant Does not require magnetic Requires external magnet IJ06, IJ16 field magnetic field. The Lorenz force in a materials to be integrated in the Current densities may be high, resulting in current carrying wire is used to move the print head manufacturing process electromigration problems actuator. Pulsed magnetic A pulsed magnetic field is used to Very low power operation is Complex print head construction IJ10 field cyclically attract a paddle, which pushes possible Magnetic materials required in print head on the ink. A small actuator moves a Small print head size catch, which selectively prevents the paddle from moving.

Actuator amplification or modification method Actuator amplification Description Advantages Disadvantages Examples None No actuator mechanical amplification is Operational simplicity Many actuator mechanisms have insufficient Thermal Bubble Inkjet used. The actuator directly drives the travel, or insufficient force, to efficiently drive IJ01, IJ02, IJ06, IJ07 drop ejection process. the drop ejection process IJ16, IJ25, IJ26 Differential An actuator material expands more on Provides greater travel in a High stresses are involved Piezoelectric expansion bend one side than on the other. The reduced print head area Care must be taken that the materials do not IJ03, IJ09, IJ17-IJ24 actuator expansion may be thermal, piezoelectric, The bend actuator converts a high delaminate IJ27, IJ29-IJ39, IJ42, magnetostrictive, or other mechanism, force low travel actuator Residual bend resulting from high temperature IJ43, IJ44 mechanism to high travel, lower force or high stress during formation mechanism. Transient bend A trilayer bend actuator where the two Very good temperature stability High stresses are involved IJ40, IJ41 actuator outside layers are identical. This cancels High speed, as a new drop can be Care must be taken that the materials do not bend due to ambient temperature and fired before heat dissipates delaminate residual stress. The actuator only Cancels residual stress of responds to transient heating of one side or the other. formation Actuator stack A series of thin actuators are stacked. Increased travel Increased fabrication complexity Some piezoelectric ink jets IJ04 This can be appropriate where actuators Reduced drive voltage Increased possibility of short circuits due to require high electric field strength, such pinholes as electrostatic and piezoelectric actuators. Multiple actuators Multiple smaller actuators are used Increases the force available from Actuator forces may not add linearly, reducing efficiency IJ12, IJ13, IJ18, IJ20 simultaneously to move the ink. Each an actuator IJ22, IJ28, IJ42, IJ43 actuator need provide only a portion of Multiple actuators can be the force required. positioned to control ink flow accurately Linear Spring A linear spring is used to transform a Matches low travel actuator with Requires print head area for the spring IJ15 motion with small travel and high force higher travel requirements into a longer travel, lower force motion. Non-contact method of motion transformation Reverse spring The actuator loads a spring. When the Better coupling to the ink Fabrication complexity IJ05, IJ11 actuator is turned off, the spring releases. High stress in the spring This can reverse the force/distance curve of the actuator to make it compatible with the force/time requirements of the drop ejection. Coiled actuator A bend actuator is coiled to provide Increases travel Generally restricted to planar implementations IJ17, IJ21, IJ34, IJ35 greater travel in a reduced integrated Reduces integrated circuit area due to extreme fabrication difficulty in other circuit area. Planar implementations are orientations. relatively easy to fabricate. Flexure bend A bend actuator has a small region near Simple means of increasing travel Care must be taken not to exceed the elastic IJ10, IJ19, IJ33 actuator the fixture point, which flexes much of a bend actuator limit in the flexure area more readily than the remainder of the Stress distribution is very uneven actuator. The actuator flexing is Difficult to accurately model with finite effectively converted from an even element analysis coiling to an angular bend, resulting in greater travel of the actuator tip. Gears Gears can be used to increase travel at Low force, low travel actuators Moving parts are required IJ13 the expense of duration. Circular gears, can be used Several actuator cycles are required rack and pinion, ratchets, and other Can be fabricated using standard More complex drive electronics gearing methods can be used. surface MEMS processes Complex construction Friction, friction, and wear are possible Catch The actuator controls a small catch. The Very low actuator energy Complex construction IJ10 catch either enables or disables Very small actuator size Requires external force movement of an ink pusher that is Unsuitable for pigmented inks controlled in a bulk manner. Buckle plate A buckle plate can be used to change a Very fast movement achievable Must stay within elastic limits of the materials S. Hirata et al, “An Ink-jet slow actuator into a fast motion. It can for long device life Head . . . ”, Proc. IEEE also convert a high force, low travel High stresses involved MEMS, February 1996, pp actuator into a high travel, medium force Generally high power requirement 418-423. motion. IJ18, IJ27 Tapered magnetic A tapered magnetic pole can increase Linearizes the magnetic Complex construction IJ14 pole travel at the expense of force. force/distance curve Lever A lever and fulcrum is used to transform Matches low travel actuator with High stress around the fulcrum IJ32, IJ36, IJ37 a motion with small travel and high force higher travel requirements into a motion with longer travel and Fulcrum area has no linear lower force. The lever can also reverse movement, and can be used for a the direction of travel. fluid seal Rotary impeller The actuator is connected to a rotary High mechanical advantage Complex construction IJ28 impeller. A small angular deflection of The ratio of force to travel of the Unsuitable for pigmented inks the actuator results in a rotation of the actuator can be matched to the impeller vanes, which push the ink nozzle requirements by varying against stationary vanes and out of the the number of impeller vanes nozzle. Acoustic lens A refractive or diffractive (e.g. zone No moving parts Large area required 1993 Hadimioglu et al, plate) acoustic lens is used to concentrate Only relevant for acoustic ink jets EUP 550,192 sound waves. 1993 Elrod et al, EUP 572,220 Sharp conductive A sharp point is used to concentrate an Simple construction Difficult to fabricate using standard VLSI Tone-jet point electrostatic field. processes for a surface ejecting ink-jet Only relevant for electrostatic ink jets

Actuator motion Actuator motion Description Advantages Disadvantages Examples Volume expansion The volume of the actuator changes, Simple construction in the case of thermal ink jet High energy is typically required to achieve Hewlett-Packard Thermal pushing the ink in all directions. volume expansion. This leads to thermal Inkjet stress, cavitation, and kogation in thermal ink Canon Bubblejet jet implementations Linear, normal to The actuator moves in a direction normal Efficient coupling to ink drops High fabrication complexity may be required IJ01, IJ02, IJ04, IJ07 integrated circuit to the print head surface. The nozzle is ejected normal to the surface to achieve perpendicular motion IJ11, IJ14 surface typically in the line of movement. Linear, parallel to The actuator moves parallel to the print Suitable for planar fabrication Fabrication complexity IJ12, IJ13, IJ15, IJ33, integrated circuit head surface. Drop ejection may still be Friction IJ34, IJ35, IJ36 surface normal to the surface. Stiction Membrane push An actuator with a high force but small The effective area of the actuator Fabrication complexity 1982 Howkins U.S. Pat. No. area is used to push a stiff membrane that becomes the membrane area Actuator size 4,459,601 is in contact with the ink. Difficulty of integration in a VLSI process Rotary The actuator causes the rotation of some Rotary levers may be used to Device complexity IJ05, IJ08, IJ13, IJ28 element, such a grill or impeller increase travel May have friction at a pivot point Small integrated circuit area requirements Bend The actuator bends when energized. This A very small change in Requires the actuator to be made from at least 1970 Kyser et al U.S. Pat. No. may be due to differential thermal dimensions can be converted to a two distinct layers, or to have a thermal 3,946,398 expansion, piezoelectric expansion, large motion. difference across the actuator 1973 Stemme U.S. Pat. No. magnetostriction, or other form of 3,747,120 relative dimensional change. IJ03, IJ09, IJ10, IJ19 IJ23, IJ24, IJ25, IJ29 IJ30, IJ31, IJ33, IJ34 IJ35 Swivel The actuator swivels around a central Allows operation where the net Inefficient coupling to the ink motion IJ06 pivot. This motion is suitable where there linear force on the paddle is zero are opposite forces applied to opposite Small integrated circuit area sides of the paddle, e.g. Lorenz force. requirements Straighten The actuator is normally bent, and Can be used with shape memory Requires careful balance of stresses to ensure IJ26, IJ32 straightens when energized. alloys where the austenic phase is that the quiescent bend is accurate planar Double bend The actuator bends in one direction when One actuator can be used to Difficult to make the drops ejected by both IJ36, IJ37, IJ38 one element is energized, and bends the power two nozzles. bend directions identical. other way when another element is Reduced integrated circuit size. A small efficiency loss compared to energized. Not sensitive to ambient equivalent single bend actuators. temperature Shear Energizing the actuator causes a shear Can increase the effective travel Not readily applicable to other actuator 1985 Fishbeck U.S. Pat. No. motion in the actuator material. of piezoelectric actuators mechanisms 4,584,590 Radial constriction The actuator squeezes an ink reservoir, Relatively easy to fabricate single High force required 1970 Zoltan U.S. Pat. No. forcing ink from a constricted nozzle. nozzles from glass tubing as Inefficient 3,683,212 macroscopic structures Difficult to integrate with VLSI processes Coil/uncoil A coiled actuator uncoils or coils more Easy to fabricate as a planar VLSI Difficult to fabricate for non-planar devices IJ17, IJ21, IJ34, IJ35 tightly. The motion of the free end of the process Poor out-of-plane stiffness actuator ejects the ink. Small area required, therefore low cost Bow The actuator bows (or buckles) in the Can increase the speed of travel Maximum travel is constrained IJ16, IJ18, IJ27 middle when energized. Mechanically rigid High force required Push-Pull Two actuators control a shutter. One The structure is pinned at both Not readily suitable for inkjets which directly IJ18 actuator pulls the shutter, and the other ends, so has a high out-of-plane push the ink pushes it. rigidity Curl inwards A set of actuators curl inwards to reduce Good fluid flow to the region Design complexity IJ20, IJ42 the volume of ink that they enclose. behind the actuator increases efficiency Curl outwards A set of actuators curl outwards, Relatively simple construction Relatively large integrated circuit area IJ43 pressurizing ink in a chamber surrounding the actuators, and expelling ink from a nozzle in the chamber. Iris Multiple vanes enclose a volume of ink. High efficiency High fabrication complexity IJ22 These simultaneously rotate, reducing Small integrated circuit area Not suitable for pigmented inks the volume between the vanes. Acoustic vibration The actuator vibrates at a high frequency. The actuator can be physically Large area required for efficient operation at 1993 Hadimioglu et al, distant from the ink useful frequencies EUP 550,192 Acoustic coupling and crosstalk 1993 Elrod et al, EUP Complex drive circuitry 572,220 Poor control of drop volume and position None In various ink jet designs the actuator does not move. No moving parts Various other tradeoffs are required to Silverbrook, EP 0771 658 A2 and eliminate moving parts related patent applications Tone-jet

Nozzle refill method Nozzle refill method Description Advantages Surface tension After the actuator is energized, it Fabrication simplicity typically returns rapidly to its normal Operational simplicity position. This rapid return sucks in air through the nozzle opening. The ink surface tension at the nozzle then exerts a small force restoring the meniscus to a minimum area. Shuttered Ink to the nozzle chamber is provided at High speed oscillating ink pressure a pressure that oscillates at twice the Low actuator energy, as the drop ejection frequency. When a drop is actuator need only open or close to be ejected, the shutter is opened for 3 the shutter, instead of ejecting the half cycles: drop ejection, actuator ink drop return, and refill. Refill actuator After the main actuator has ejected a High speed, as the nozzle is drop a second (refill) actuator is actively refilled energized. The refill actuator pushes ink into the nozzle chamber. The refill actuator returns slowly, to prevent its return from emptying the chamber again. Positive ink The ink is held a slight positive pressure. High refill rate, therefore a high pressure After the ink drop is ejected, the nozzle drop repetition rate is possible chamber fills quickly as surface tension and ink pressure both operate to refill the nozzle. Nozzle refill method Disadvantages Examples Surface tension Low speed Thermal inkjet Surface tension force relatively small Piezoelectric inkjet compared to actuator force IJ01-IJ07, IJ10-IJ14 Long refill time usually dominates the total repetition rate IJ16, IJ20, IJ22-IJ45 Shuttered Requires common ink pressure oscillator IJ08, IJ13, IJ15, IJ17 oscillating ink pressure May not be suitable for pigmented inks IJ18, IJ19, IJ21 Refill actuator Requires two independent actuators per nozzle IJ09 Positive ink Surface spill must be prevented Silverbrook, EP 0771 658 pressure Highly hydrophobic print head surfaces are A2 and related patent required applications Alternative for: IJ01-IJ07, IJ10-IJ14 IJ16, IJ20, IJ22-IJ45

Method of restricting back-flow through inlet Inlet back-flow restriction method Description Advantages Disadvantages Examples Long inlet channel The ink inlet channel to the nozzle Design simplicity Restricts refill rate Thermal inkjet chamber is made long and relatively Operational simplicity May result in a relatively large integrated Piezoelectric inkjet narrow, relying on viscous drag to reduce inlet back-flow. Reduces crosstalk circuit area IJ42, IJ43 Only partially effective Positive ink pressure The ink is under a positive pressure, so that in the Drop selection and separation Requires a method (such as a nozzle rim or Silverbrook, EP 0771 658 quiescent state some of the ink drop already protrudes forces can be reduced effective hydrophobizing, or both) to prevent A2 and related patent applications from the nozzle. This reduces the pressure in the Fast refill time flooding of the ejection surface of the print Possible operation of the following: nozzle chamber which is required to eject a certain head. IJ01-IJ07, IJ09-IJ12 volume of ink. The reduction in chamber pressure results IJ14, IJ16, IJ20, IJ22, in a reduction in ink pushed out through the inlet. IJ23-IJ34, IJ36-IJ41 IJ44 Baffle One or more baffles are placed in the inlet ink flow. The refill rate is not as restricted Design complexity HP Thermal Ink Jet When the actuator is energized, the rapid ink movement as the long inlet method. May increase fabrication complexity (e.g. Tektronix piezoelectric ink creates eddies which restrict the flow through the inlet. Reduces crosstalk Tektronix hot melt Piezoelectric print heads). jet The slower refill process is unrestricted, and does not result in eddies. Flexible flap restricts inlet In this method recently disclosed by Significantly reduces back-flow Not applicable to most inkjet configurations Canon Canon, the expanding actuator (bubble) for edge-shooter thermal ink jet Increased fabrication complexity pushes on a flexible flap that restricts the devices Inelastic deformation of polymer flap results inlet. in creep over extended use Inlet filter A filter is located between the ink inlet and the Additional advantage of ink Restricts refill rate IJ04, IJ12, IJ24, IJ27 nozzle chamber. The filter has a multitude of small holes filtration May result in complex construction IJ29, IJ30 or slots, restricting ink flow. The filter also Ink filter may be fabricated with removes particles which may block the nozzle. no additional process steps Small inlet compared to nozzle The ink inlet channel to the nozzle Design simplicity Restricts refill rate IJ02, IJ37, IJ44 chamber has a substantially smaller cross May result in a relatively large integrated section than that of the nozzle, resulting in easier circuit area ink egress out of the nozzle than out of the inlet. Only partially effective Inlet shutter A secondary actuator controls the position of a shutter, Increases speed of the ink-jet print Requires separate refill actuator and drive IJ09 closing off the ink inlet when the main actuator is head operation circuit energized. The inlet is located behind the The method avoids the problem of inlet Back-flow problem is eliminated Requires careful design to minimize the IJ01, IJ03, IJ05, IJ06 ink-pushing surface back-flow by arranging the ink-pushing negative pressure behind the paddle IJ07, IJ10, IJ11, IJ14 surface of the actuator between the inlet IJ16, IJ22, IJ23, IJ25 and the nozzle. IJ28, IJ31, IJ32, IJ33 IJ34, IJ35, IJ36, IJ39 IJ40, IJ41 Part of the actuator moves to The actuator and a wall of the ink Significant reductions in back- Small increase in fabrication complexity IJ07, IJ20, IJ26, IJ38 shut off the inlet chamber are arranged so that the motion flow can be achieved of the actuator closes off the inlet. Compact designs possible Nozzle actuator does not result In some configurations of ink jet, there is Ink back-flow problem is None related to ink back-flow on actuation Silverbrook, EP 0771 658 in ink back-flow no expansion or movement of an actuator eliminated A2 and related patent which may cause ink back-flow through applications the inlet. Valve-jet Tone-jet IJ08, IJ13, IJ15, IJ17 IJ18, IJ19, IJ21

Nozzle Clearing Method Nozzle Clearing method Description Advantages Disadvantages Examples Normal nozzle firing All of the nozzles are fired periodically, before the No added complexity on the print head May not be sufficient to displace dried ink Most ink jet systems ink has a chance to dry. When not in use the nozzles IJ01-IJ07, IJ09-IJ12 are sealed (capped) against air. The nozzle firing is usually IJ14, IJ16, IJ20, IJ22 performed during a special clearing cycle, after first IJ23-IJ34, IJ36-IJ45 moving the print head to a cleaning station. Extra power to ink heater In systems which heat the ink, but do not Can be highly effective if the Requires higher drive voltage for clearing Silverbrook, EP 0771 658 boil it under normal situations, nozzle heater is adjacent to the nozzle May require larger drive transistors A2 and related patent clearing can be achieved by over- applications powering the heater and boiling ink at the nozzle. Rapid succession The actuator is fired in rapid succession. Does not require extra drive Effectiveness depends substantially upon the May be used with: of actuator pulses In some configurations, this may cause circuits on the print head configuration of the inkjet nozzle IJ01-IJ07, IJ09-IJ11 heat build-up at the nozzle which boils Can be readily controlled and IJ14, IJ16, IJ20, IJ22 the ink, clearing the nozzle. In other initiated by digital logic IJ23-IJ25, IJ27-IJ34 IJ36-IJ45 situations, it may cause sufficient vibrations to dislodge clogged nozzles. Extra power to ink Where an actuator is not normally driven A simple solution where applicable Not suitable where there is a hard limit to May be used with: pushing actuator to the limit of its motion, nozzle clearing actuator movement IJ03, IJ09, IJ16, IJ20 may be assisted by providing an IJ23, IJ24, IJ25, IJ27 enhanced drive signal to the actuator. IJ29, IJ30, IJ31, IJ32 IJ39, IJ40, IJ41, IJ42 IJ43, IJ44, IJ45 Acoustic resonance An ultrasonic wave is applied to the ink chamber. This A high nozzle clearing capability High implementation cost if system does not IJ08, IJ13, IJ15, IJ17 wave is of an appropriate amplitude and frequency can be achieved already include an acoustic actuator IJ18, IJ19, IJ21 to cause sufficient force at the nozzle to clear blockages. May be implemented at very low This is easiest to achieve if the ultrasonic wave cost in systems which already is at a resonant frequency of the ink cavity. include acoustic actuators Nozzle clearing plate A microfabricated plate is pushed against Can clear severely clogged nozzles Accurate mechanical alignment is required Silverbrook, EP 0771 658 the nozzles. The plate has a post for Moving parts are required A2 and related patent every nozzle. The array of posts There is risk of damage to the nozzles applications Accurate fabrication is required Ink pressure pulse The pressure of the ink is temporarily May be effective where other Requires pressure pump or other pressure May be used with all IJ increased so that ink streams from all of methods cannot be used actuator series ink jets the nozzles. This may be used in Expensive conjunction with actuator energizing. Wasteful of ink Print head wiper A flexible ‘blade’ is wiped across the Effective for planar print head Difficult to use if print head surface is non- Many ink jet systems print head surface. The blade is usually surfaces planar or very fragile fabricated from a flexible polymer, e.g. Low cost Requires mechanical parts rubber or synthetic elastomer. Blade can wear out in high volume print systems Separate ink A separate heater is provided at the Can be effective where other Fabrication complexity Can be used with many IJ boiling heater nozzle although the normal drop e-ection nozzle clearing methods cannot series ink jets mechanism does not require it. The be used heaters do not require individual drive Can be implemented at no additional circuits, as many nozzles can be cleared cost in some inkjet configurations simultaneously, and no imaging is required.

Nozzle plate construction Nozzle plate construction Description Advantages Disadvantages Examples Electroformed nickel A nozzle plate is separately fabricated Fabrication simplicity High temperatures and pressures are required Hewlett Packard Thermal Inkjet from electroformed nickel, and bonded to bond nozzle plate to the print head integrated circuit. Minimum thickness constraints Differential thermal expansion Laser ablated or drilled polymer Individual nozzle holes are ablated by an No masks required Each hole must be individually formed Canon Bubblejet intense UV laser in a nozzle plate, which Can be quite fast Special equipment required 1988 Sercel et al., SPIE, is typically a polymer such as polyimide Some control over nozzle profile Slow where there are many thousands of Vol. 998 Excimer Beam or polysulphone is possible nozzles per print head Applications, pp. 76-83 Equipment required is relatively May produce thin burrs at exit holes 1993 Watanabe et al., U.S. Pat. No. 5,208,604 low cost Silicon micro-machined A separate nozzle plate is micro- High accuracy is attainable Two part construction K. Bean, IEEE machined from single crystal silicon, High cost Transactions on Electron Devices, Vol. ED-25, and bonded to the print head wafer. Requires precision alignment No. 10, 1978, pp 1185-1195 Nozzles may be clogged by adhesive Xerox 1990 Hawkins et al., U.S. Pat. No. 4,899,181 Glass capillaries Fine glass capillaries are drawn from No expensive equipment required Very small nozzle sizes are difficult to form 1970 Zoltan U.S. Pat. No. 3,683,212 glass tubing. This method has been used Simple to make single nozzles Not suited for mass production for making individual nozzles, but is difficult to use for bulk manufacturing of print heads with thousands of nozzles. Monolithic, surface micro- The nozzle plate is deposited as a layer High accuracy (<1 μm) Requires sacrificial layer under the nozzle Silverbrook, EP 0771 658 machined using VLSI using standard VLSI deposition Monolithic plate to form the nozzle chamber A2 and related patent lithographic processes techniques. Nozzles are etched in the Low cost Surface may be fragile to the touch applications nozzle plate using VLSI lithography and Existing processes can be used IJ01, IJ02, IJ04, IJ11 etching. IJ12, IJ17, IJ18, IJ20 IJ22, IJ24, IJ27, IJ28 IJ29, IJ30, IJ31, IJ32 IJ33, IJ34, IJ36, IJ37 IJ38, IJ39, IJ40, IJ41 IJ42, IJ43, IJ44 Monolithic, etched The nozzle plate is a buried etch stop in High accuracy (<1 μm) Requires long etch times IJ03, IJ05, IJ06, IJ07 through substrate the wafer. Nozzle chambers are etched in Monolithic Requires a support wafer IJ08, IJ09, IJ10, IJ13 the front of the wafer, and the wafer is Low cost IJ14, IJ15, IJ16, IJ19 thinned from the back side. Nozzles are No differential expansion IJ21, IJ23, IJ25, IJ26 then etched in the etch stop layer. No nozzle plate Various methods have been tried to No nozzles to become clogged Difficult to control drop position accurately Ricoh 1995 Sekiya et al eliminate the nozzles entirely, to prevent Crosstalk problems U.S. Pat. No. 5,412,413 nozzle clogging. These include thermal 1993 Hadimioglu et al bubble mechanisms and acoustic lens EUP 550,192 mechanisms 1993 Elrod et al EUP 572,220 Trough Each drop ejector has a trough through which Reduced manufacturing complexity Drop firing direction is sensitive to wicking. IJ35 a paddle moves. There is no nozzle plate. Monolithic Nozzle slit instead The elimination of nozzle holes and No nozzles to become clogged Difficult to control drop position accurately 1989 Saito et al U.S. Pat. No. 4,799,068 of individual replacement by a slit encompassing Crosstalk problems nozzles many actuator positions reduces nozzle clogging, but increases crosstalk due to ink surface waves

Drop ejection direction Ejection direction Description Advantages Disadvantages Examples Edge Ink flow is along the surface of the Simple construction Nozzles limited to edge Canon Bubblejet 1979 (‘edge integrated circuit, and ink drops are No silicon etching required High resolution is difficult Endo et al GB patent shooter’) ejected from the integrated circuit edge. Good heat sinking via substrate Fast color printing requires 2,007,162 Mechanically strong one print head per color Xerox heater-in-pit Ease of integrated circuit handing 1990 Hawkins et al U.S. Pat. No. 4,899,181 Tone-jet Surface Ink flow is along the surface of the No bulk silicon etching required Maximum ink flow is Hewlett-Packard TIJ (‘roof shooter’) integrated circuit, and ink drops are Silicon can make an effective heat severely restricted 1982 Vaught et al ejected from the integrated circuit sink U.S. Pat. No. surface, normal to the plane of the Mechanical strength 4,490,728 IJ02, integrated circuit. IJ11, IJ12, IJ20 IJ22 Through Ink flow is through the integrated circuit, High ink flow Requires bulk silicon etching Silverbrook, integrated and ink drops are ejected from the front Suitable for pagewidth print EP 0771 658 A2 circuit, forward surface of the integrated circuit. High nozzle packing density and related patent (‘up shooter’) therefore low manufacturing cost applications IJ04, IJ17, IJ18, IJ24 IJ27-IJ45 Through Ink flow is through the integrated circuit, High ink flow Requires wafer thinning IJ01, IJ03, IJ05, IJ06 integrated and ink drops are ejected from the rear Suitable for pagewidth print Requires special handling IJ07, IJ08, IJ09, IJ10 circuit, reverse surface of the integrated circuit. High nozzle packing density during manufacture IJ13, IJ14, IJ15, IJ16 (‘down therefore low manufacturing cost IJ19, IJ21, IJ23, IJ25 shooter’) IJ26 Through Ink flow is through the actuator, which is Suitable for piezoelectric print Pagewidth print heads Epson Stylus actuator not fabricated as part of the same heads require several thousand Tektronix hot melt substrate as the drive transistors. connections to drive circuits piezoelectric ink jets Cannot be manufactured in standard CMOS fabs Complex assembly required

Ink type Ink type Description Advantages Disadvantages Examples Aqueous, Water based ink which typically Environmentally friendly Slow drying Most existing inkjets dye contains: water, dye, surfactant, No odor Corrosive All IJ series ink jets humectant, and biocide. Bleeds on paper Silverbrook, EP 0771 658 Modern ink dyes have high water- May strikethrough A2 and related patent fastness, light fastness Cockles paper applications Aqueous, Water based ink which typically Environmentally friendly Slow drying IJ02, IJ04, IJ21, IJ26 pigment contains: water, pigment, surfactant, No odor Corrosive IJ27, IJ30 humectant, and biocide. Reduced bleed Pigment may clog nozzles Silverbrook, EP 0771 658 Pigments have an advantage in reduced Reduced wicking Pigment may clog actuator A2 and related patent bleed, wicking and strikethrough. Reduced strikethrough mechanisms applications Cockles paper Piezoelectric ink-jets Thermal ink jets (with significant restrictions) Methyl Ethyl MEK is a highly volatile solvent used for Very fast drying Odorous All IJ series ink jets Ketone industrial printing on difficult surfaces Prints on various substrates such Flammable (MEK) such as aluminum cans. as metals and plastics Alcohol Alcohol based inks can be used where Fast drying Slight odor All IJ series ink jets (ethanol, the printer must operate at temperatures Operates at sub-freezing Flammable 2-butanol, below the freezing point of water. An temperatures and others) example of this is in-camera consumer Reduced paper cockle photographic printing. Low cost Phase The ink is solid at room temperature, and No drying time—ink instantly High viscosity Tektronix hot melt change is melted in the print head before jetting. freezes on the print medium Printed ink typically has piezoelectric ink jets (hot melt) Hot melt inks are usually wax based, Almost any print medium can be a ‘waxy’ feel 1989 Nowak U.S. Pat. No. with a melting point around 80° C. After used Printed pages may ‘block’ 4,820,346 jetting the ink freezes almost instantly No paper cockle occurs Ink temperature may be above All IJ series ink jets upon contacting the print medium or a No wicking occurs the curie point of transfer roller. No bleed occurs permanent magnets No strikethrough occurs Ink heaters consume power Long warm-up time Oil Oil based inks are extensively used in High solubility medium for High viscosity: this is a All IJ series ink jets offset printing. They have advantages in some dyes significant limitation improved characteristics on paper Does not cockle paper for use in inkjets, which (especially no wicking or cockle). Oil Does not wick through paper usually require a low soluble dies and pigments are required. viscosity. Some short chain and multi-branched oils have a sufficiently low viscosity. Slow drying Micro- A microemulsion is a stable, self forming Stops ink bleed Viscosity higher than water All IJ series ink jets emulsion emulsion of oil, water, and surfactant. High dye solubility Cost is slightly higher than The characteristic drop size is less than Water, oil, and amphiphilic water based ink 100 nm, and is determined by the soluble dies can be used High surfactant concentration preferred curvature of the surfactant. Can stabilize pigment required (around 5%) suspensions Ink Jet Printing

A large number of new forms of ink jet printers have been developed to facilitate alternative ink jet technologies for the image processing and data distribution system. Various combinations of ink jet devices can be included in printer devices incorporated as part of the present invention. Australian Provisional Patent Applications relating to these ink jets which are specifically incorporated by cross reference. The serial numbers of respective corresponding US patent applications are also provided for the sake of convenience. Australian US Patent/ Provisional Patent Application Number Filing Date Title and Filing Date PO8066 15-Jul-97 Image Creation Method and Apparatus (IJ01) 6,227,652 (Jul. 10, 1998) PO8072 15-Jul-97 Image Creation Method and Apparatus (IJ02) 6,213,588 (Jul. 10, 1998) PO8040 15-Jul-97 Image Creation Method and Apparatus (IJ03) 6,213,589 (July 10, 1998) PO8071 15-Jul-97 Image Creation Method and Apparatus (IJ04) 6,231,163 (Jul. 10, 1998) PO8047 15-Jul-97 Image Creation Method and Apparatus (IJ05) 6,247,795 (Jul. 10, 1998) PO8035 15-Jul-97 Image Creation Method and Apparatus (IJ06) 6,394,581 (Jul. 10, 1998) PO8044 15-Jul-97 Image Creation Method and Apparatus (IJ07) 6,244,691 (Jul. 10, 1998) PO8063 15-Jul-97 Image Creation Method and Apparatus (IJ08) 6,257,704 (Jul. 10, 1998) PO8057 15-Jul-97 Image Creation Method and Apparatus (IJ09) 6,416,168 (Jul. 10, 1998) PO8056 15-Jul-97 Image Creation Method and Apparatus (IJ10) 6,220,694 (Jul. 10, 1998 PO8069 15-Jul-97 Image Creation Method and Apparatus (IJ11) 6,257,705 (Jul. 10, 1998 PO8049 15-Jul-97 Image Creation Method and Apparatus (IJ12) 6,247,794 (Jul. 10, 1998 PO8036 15-Jul-97 Image Creation Method and Apparatus (IJ13) 6,234,610 (Jul. 10, 1998 PO8048 15-Jul-97 Image Creation Method and Apparatus (IJ14) 6,247,793 (Jul. 10, 1998 PO8070 15-Jul-97 Image Creation Method and Apparatus (IJ15) 6,264,306 (Jul. 10, 1998 PO8067 15-Jul-97 Image Creation Method and Apparatus (IJ16) 6,241,342 (Jul. 10, 1998 PO8001 15-Jul-97 Image Creation Method and Apparatus (IJ17) 6,247,792 (Jul. 10, 1998 PO8038 15-Jul-97 Image Creation Method and Apparatus (IJ18) 6,264,307 (Jul. 10, 1998 PO8033 15-Jul-97 Image Creation Method and Apparatus (IJ19) 6,254,220 (Jul. 10, 1998 PO8002 15-Jul-97 Image Creation Method and Apparatus (IJ20) 6,234,611 (Jul. 10, 1998 PO8068 15-Jul-97 Image Creation Method and Apparatus (IJ21) 6,302,528 (Jul. 10, 1998 PO8062 15-Jul-97 Image Creation Method and Apparatus (IJ22) 6,283,582 (Jul. 10, 1998 PO8034 15-Jul-97 Image Creation Method and Apparatus (IJ23) 6,239,821 (Jul. 10, 1998 PO8039 15-Jul-97 Image Creation Method and Apparatus (IJ24) 6,338,547 (Jul. 10, 1998 PO8041 15-Jul-97 Image Creation Method and Apparatus (IJ25) 6,247,796 (Jul. 10, 1998 PO8004 15-Jul-97 Image Creation Method and Apparatus (IJ26) 09/113,122 (Jul. 10, 1998 PO8037 15-Jul-97 Image Creation Method and Apparatus (IJ27) 6,390,603 (Jul. 10, 1998 PO8043 15-Jul-97 Image Creation Method and Apparatus (IJ28) 6,362,843 (Jul. 10, 1998 PO8042 15-Jul-97 Image Creation Method and Apparatus (IJ29) 6,293,653 (Jul. 10, 1998 PO8064 15-Jul-97 Image Creation Method and Apparatus (IJ30) 6,312,107 (Jul. 10, 1998 PO9389 23-Sep-97 Image Creation Method and Apparatus (IJ31) 6,227,653 (Jul. 10, 1998 PO9391 23-Sep-97 Image Creation Method and Apparatus (IJ32) 6,234,609 (Jul. 10, 1998 PP0888 12-Dec-97 Image Creation Method and Apparatus (IJ33) 6,238,040 (Jul. 10, 1998 PP0891 12-Dec-97 Image Creation Method and Apparatus (IJ34) 6,188,415 (Jul. 10, 1998 PP0890 12-Dec-97 Image Creation Method and Apparatus (IJ35) 6,227,654 (Jul. 10, 1998 PP0873 12-Dec-97 Image Creation Method and Apparatus (IJ36) 6,209,989 (Jul. 10, 1998 PP0993 12-Dec-97 Image Creation Method and Apparatus (IJ37) 6,247,791 (Jul. 10, 1998 PP0890 12-Dec-97 Image Creation Method and Apparatus (IJ38) 6,336,710 (Jul 10, 1998 PP1398 19-Jan-98 An Image Creation Method and Apparatus 6,217,153 (IJ39) (Jul. 10, 1998 PP2592 25-Mar-98 An Image Creation Method and Apparatus 6,416,167 (IJ40) (Jul. 10, 1998 PP2593 25-Mar-98 Image Creation Method and Apparatus (IJ41) 6,243,113 (Jul. 10, 1998 PP3991  9-Jun-98 Image Creation Method and Apparatus (IJ42) 6,283,581 (Jul. 10, 1998 PP3987  9-Jun-98 Image Creation Method and Apparatus (IJ43) 6,247,790 (Jul. 10, 1998 PP3985  9-Jun-98 Image Creation Method and Apparatus (IJ44) 6,260,953 (Jul. 10, 1998 PP3983  9-Jun-98 Image Creation Method and Apparatus (IJ45) 6,267,469 (Jul. 10, 1998 Ink Jet Manufacturing

Further, the present application may utilize advanced semiconductor fabrication techniques in the construction of large arrays of ink jet printers. Suitable manufacturing techniques are described in the following Australian provisional patent specifications incorporated here by cross-reference. The serial numbers of respective corresponding US patent applications are also provided for the sake of convenience. Australian US Patent/ Provisional Patent Application Number Filing Date Title and Filing Date PO7935 15-Jul-97 A Method of Manufacture of an Image Creation 6,224,780 Apparatus (IJM01) (Jul. 10, 1998) PO7936 15-Jul-97 A Method of Manufacture of an Image Creation 6,235,212 Apparatus (IJM02) (July 10, 1998) PO7937 15-Jul-97 A Method of Manufacture of an Image Creation 6,280,643 Apparatus (IJM03) (Jul. 10, 1998) PO8061 15-Jul-97 A Method of Manufacture of an Image Creation 6,284,147 Apparatus (IJM04) (Jul. 10, 1998) PO8054 15-Jul-97 A Method of Manufacture of an Image Creation 6,214,244 Apparatus (IJM05) (Jul. 10, 1998) PO8065 15-Jul-97 A Method of Manufacture of an Image Creation 6,071,750 Apparatus (IJM06) (Jul. 10, 19980 PO8055 15-Jul-97 A Method of Manufacture of an Image Creation 6,267,905 Apparatus (IJM07) (Jul. 10, 1998) PO8053 15-Jul-97 A Method of Manufacture of an Image Creation 6,251,298 Apparatus (IJM08) (Jul. 10, 1998) PO8078 15-Jul-97 A Method of Manufacture of an Image Creation 6,258,285 Apparatus (IJM09) (Jul. 10, 1998) PO7933 15-Jul-97 A Method of Manufacture of an Image Creation 6,225,138 Apparatus (IJM10) (Jul. 10, 1998) PO7950 15-Jul-97 A Method of Manufacture of an Image Creation 6,241,904 Apparatus (IJM11) (Jul. 10, 1998) PO7949 15-Jul-97 A Method of Manufacture of an Image Creation 6,299,786 Apparatus (IJM12) (Jul. 10, 1998) PO8060 15-Jul-97 A Method of Manufacture of an Image Creation 09/113,124 Apparatus (IJM13) (Jul. 10, 1998) PO8059 15-Jul-97 A Method of Manufacture of an Image Creation 6,231,773 Apparatus (IJM14) (Jul. 10, 1998) PO8073 15-Jul-97 A Method of Manufacture of an Image Creation 6,190,931 Apparatus (IJM15) (Jul. 10, 1998) PO8076 15-Jul-97 A Method of Manufacture of an Image Creation 6,248,249 Apparatus (IJM16) (Jul. 10, 1998) PO8075 15-Jul-97 A Method of Manufacture of an Image Creation 6,290,862 Apparatus (IJM17) (Jul. 10, 1998) PO8079 15-Jul-97 A Method of Manufacture of an Image Creation 6,241,906 Apparatus (IJM18) (Jul. 10, 1998) PO8050 15-Jul-97 A Method of Manufacture of an Image Creation 09/113,116 Apparatus (IJM19) (Jul. 10, 1998) PO8052 15-Jul-97 A Method of Manufacture of an Image Creation 6,241,905 Apparatus (IJM20) (Jul. 10, 1998) PO7948 15-Jul-97 A Method of Manufacture of an Image Creation 6,451,216 Apparatus (IJM21) (Jul. 10, 1998) PO7951 15-Jul-97 A Method of Manufacture of an Image Creation 6,231,772 Apparatus (IJM22) (Jul. 10, 1998) PO8074 15-Jul-97 A Method of Manufacture of an Image Creation 6,274,056 Apparatus (IJM23) (Jul. 10, 1998) PO7941 15-Jul-97 A Method of Manufacture of an Image Creation 6,290,861 Apparatus (IJM24) (Jul. 10, 1998) PO8077 15-Jul-97 A Method of Manufacture of an Image Creation 6,248,248 Apparatus (IJM25) (Jul. 10, 1998) PO8058 15-Jul-97 A Method of Manufacture of an Image Creation 6,306,671 Apparatus (IJM26) (Jul. 10, 1998) PO8051 15-Jul-97 A Method of Manufacture of an Image Creation 6,331,258 Apparatus (IJM27) (Jul. 10, 1998) PO8045 15-Jul-97 A Method of Manufacture of an Image Creation 6,110,754 Apparatus (IJM28) (Jul. 10, 1998) PO7952 15-Jul-97 A Method of Manufacture of an Image Creation 6,294,101 Apparatus (IJM29) (Jul. 10, 1998) PO8046 15-Jul-97 A Method of Manufacture of an Image Creation 6,416,679 Apparatus (IJM30) (Jul. 10, 1998) PO8503 11-Aug-97 A Method of Manufacture of an Image Creation 6,264,849 Apparatus (IJM30a) (Jul. 10, 1998) PO9390 23-Sep-97 A Method of Manufacture of an Image Creation 6,254,793 Apparatus (IJM31) (Jul. 10, 1998) PO9392 23-Sep-97 A Method of Manufacture of an Image Creation 6,235,211 Apparatus (IJM32) (Jul. 10, 1998) PP0889 12-Dec-97 A Method of Manufacture of an Image Creation 6,235,211 Apparatus (IJM35) (Jul. 10, 1998) PP0887 12-Dec-97 A Method of Manufacture of an Image Creation 6,264,850 Apparatus (IJM36) (Jul. 10, 1998) PP0882 12-Dec-97 A Method of Manufacture of an Image Creation 6,258,284 Apparatus (IJM37) (Jul. 10, 1998) PP0874 12-Dec-97 A Method of Manufacture of an Image Creation 6,258,284 Apparatus (IJM38) (Jul. 10, 1998) PP1396 19-Jan-98 A Method of Manufacture of an Image Creation 6,228,668 Apparatus (IJM39) (Jul. 10, 1998) PP2591 25-Mar-98 A Method of Manufacture of an Image Creation 6,180,427 Apparatus (IJM41) (Jul. 10, 1998) PP3989  9-Jun-98 A Method of Manufacture of an Image Creation 6,171,875 Apparatus (IJM40) (Jul. 10, 1998) PP3990  9-Jun-98 A Method of Manufacture of an Image Creation 6,267,904 Apparatus (IJM42) (Jul. 10, 1998) PP3986  9-Jun-98 A Method of Manufacture of an Image Creation 6,245,247 Apparatus (IJM43) (Jul. 10, 1998) PP3984  9-Jun-98 A Method of Manufacture of an Image Creation 6,245,247 Apparatus (IJM44) (Jul. 10, 1998) PP3982  9-Jun-98 A Method of Manufacture of an Image Creation 6,231,148 Apparatus (IJM45) (Jul. 10, 1998) Fluid Supply

Further the present application may utilize an ink delivery system to the ink jet head. Delivery systems relating to the supply of ink to a series of ink jet nozzles are described in the following Australian provisional patent specifications, the disclosure of which are hereby incorporated by cross-reference. The serial numbers of respective corresponding US patent applications are also provided for the sake of convenience. Australian US Patent/Patent Provisional Application and Number Filing Date Title Filing Date PO8003 15-Jul-97 Supply method 6,350,023 and Apparatus (F1) (Jul. 10, 1998) PO8005 15-Jul-97 Supply method 6,318,849 and Apparatus (F2) (Jul. 10, 1998) MEMS Technology

Further, the present application may utilize advanced semiconductor microelectromechanical techniques in the construction of large arrays of ink jet printers. Suitable microelectromechanical techniques are described in the following Australian provisional patent specifications incorporated here by cross-reference. The serial numbers of respective corresponding US patent applications are also provided for the sake of convenience. Australian US Patent/Patent Provisional Application and Number Filing Date Title Filing Date PO8006 15-Jul-97 A device (MEMS02) 6,087,638 (Jul. 10, 1998) PO8007 15-Jul-97 A device (MEMS03) 09/113,093 (July 10, 1998) PO8008 15-Jul-97 A device (MEMS04) 6,340,222 (Jul. 10, 1998) PO8010 15-Jul-97 A device (MEMS05) 6,041,600 (Jul. 10, 1998) PO8011 15-Jul-97 A device (MEMS06) 6,299,300 (Jul. 10, 1998) PO7947 15-Jul-97 A device (MEMS07) 6,067,797 (Jul. 10, 1998) PO7944 15-Jul-97 A device (MEMS09) 6,286,935 (Jul. 10, 1998) PO7946 15-Jul-97 A device (MEMS10) 6,044,646 (Jul. 10, 1998) PO9393 23-Sep-97 A Device and Method 09/113,065 (MEMS11) (Jul. 10, 1998) PP0875 12-Dec-97 A Device (MEMS12) 09/113,078 (Jul. 10, 1998) PP0894 12-Dec-97 A Device and Method 6,382,769 (MEMS13) (Jul. 10, 1998) IR Technologies

Further, the present application may include the utilization of a disposable camera system such as those described in the following Australian provisional patent specifications incorporated here by cross-reference. The serial numbers of respective corresponding US patent applications are also provided for the sake of convenience. Australian US Patent/Patent Provisional Application and Number Filing Date Title Filing Date PP0895 12-Dec-97 An Image Creation 6,231,148 Method and (Jul. 10, 1998) Apparatus (IR01) PP0870 12-Dec-97 A Device and Method 09/113,106 (IR02) (July 10, 1998) PP0869 12-Dec-97 A Device and Method 6,293,658 (IR04) (Jul. 10, 1998) PP0887 12-Dec-97 Image Creation 6,614,560 Method and (Jul. 10, 1998) Apparatus (IR05) PP0885 12-Dec-97 An Image Production 6,238,033 System (IR06) (Jul. 10, 1998) PP0884 12-Dec-97 Image Creation 6,312,070 Method and (Jul. 10, 1998) Apparatus (IR10) PP0886 12-Dec-97 Image Creation 6,238,111 Method and (Jul. 10, 1998) Apparatus (IR12) PP0871 12-Dec-97 A Device and 09/113,086 Method (IR13) (Jul. 10, 1998) PP0876 12-Dec-97 An Image Processing 09/113,094 Method and (Jul. 10, 1998) Apparatus (IR14) PP0877 12-Dec-97 A Device and 6,378,970 Method (IR16) (Jul. 10, 1998 PP0878 12-Dec-97 A Device and 6,196,739 Method (IR17) (Jul. 10, 1998) PP0883 12-Dec-97 A Device and 6,270,182 Method (IR19) (Jul. 10, 1998) PP0880 12-Dec-97 A Device and 6,152,619 Method (IR20) (Jul. 10, 1998) PP0881 12-Dec-97 A Device and 09/113,092 Method (IR21) (Jul. 10, 1998) DotCard Technologies

Further, the present application may include the utilization of a data distribution system such as that described in the following Australian provisional patent specifications incorporated here by cross-reference. The serial numbers of respective corresponding US patent applications are also provided for the sake of convenience. Australian US Patent/Patent Provisional Application and Number Filing Date Title Filing Date PP2370 16-Mar-98 Data Processing Method 6,786,420 and Apparatus (Dot01) (Jul. 10, 1998) PP2371 16-Mar-98 Data Processing Method 09/113,052 and Apparatus (Dot02) (Jul. 10, 1998) Artcam Technologies

Further, the present application may include the utilization of camera and data processing techniques such as an Artcam type device as described in the following Australian provisional patent specifications incorporated here by cross-reference. The serial numbers of respective corresponding US patent applications are also provided for the sake of convenience. Australian Provisional US Patent/Patent Application and Number Filing Date Title Filing Date PO7991 15-Jul-97 Image Processing Method and Apparatus 6,750,901 (ART01) (Jul. 10, 1998) PO7988 15-Jul-97 Image Processing Method and Apparatus 6,476,863 (ART02) (Jul. 10, 1998) PO7993 15-Jul-97 Image Processing Method and Apparatus 6,788,336 (ART03) (Jul. 10, 1998) PO9395 23-Sep-97 Data Processing Method and Apparatus 6,322,181 (ART04) (Jul. 10, 1998) PO8017 15-Jul-97 Image Processing Method and Apparatus 6,597,817 (ART06) (Jul. 10, 1998) PO8014 15-Jul-97 Media Device (ART07) 6,227,648 (Jul. 10, 1998) PO8025 15-Jul-97 Image Processing Method and Apparatus 6,727,948 (ART08) (Jul. 10, 1998) PO8032 15-Jul-97 Image Processing Method and Apparatus 6,690,419 (ART09) (Jul. 10, 1998) PO7999 15-Jul-97 Image Processing Method and Apparatus 6,727,951 (ART10) (Jul. 10, 1998) PO7998 15-Jul-97 Image Processing Method and Apparatus 09/112,742 (ART11) (Jul. 10, 1998) PO8031 15-Jul-97 Image Processing Method and Apparatus 09/112,741 (ART12) (Jul. 10, 1998) PO8030 15-Jul-97 Media Device (ART13) 6,196,541 (Jul. 10, 1998) PO7997 15-Jul-97 Media Device (ART15) 6,195,150 (Jul. 10, 1998) PO7979 15-Jul-97 Media Device (ART16) 6,362,868 (Jul. 10, 1998) PO8015 15-Jul-97 Media Device (ART17) 09/112,738 (Jul. 10, 1998) PO7978 15-Jul-97 Media Device (ART18) 09/113,067 (Jul. 10, 1998) PO7982 15-Jul-97 Data Processing Method and Apparatus 6,431,669 (ART19) (Jul. 10, 1998 PO7989 15-Jul-97 Data Processing Method and Apparatus 6,362,869 (ART20) (Jul. 10, 1998 PO8019 15-Jul-97 Media Processing Method and Apparatus 6,472,052 (ART21) (Jul. 10, 1998 PO7980 15-Jul-97 Image Processing Method and Apparatus 6,356,715 (ART22) (Jul. 10, 1998) PO8018 15-Jul-97 Image Processing Method and Apparatus 09/112,777 (ART24) (Jul. 10, 1998) PO7938 15-Jul-97 Image Processing Method and Apparatus 6,636,216 (ART25) (Jul. 10, 1998) PO8016 15-Jul-97 Image Processing Method and Apparatus 6,366,693 (ART26) (Jul. 10, 1998) PO8024 15-Jul-97 Image Processing Method and Apparatus 6,329,990 (ART27) (Jul. 10, 1998) PO7940 15-Jul-97 Data Processing Method and Apparatus 09/113,072 (ART28) (Jul. 10, 1998) PO7939 15-Jul-97 Data Processing Method and Apparatus 6,459,495 (ART29) (Jul. 10, 1998) PO8501 11-Aug-97 Image Processing Method and Apparatus 6,137,500 (ART30) (Jul. 10, 1998) PO8500 11-Aug-97 Image Processing Method and Apparatus 6,690,416 (ART31) (Jul. 10, 1998) PO7987 15-Jul-97 Data Processing Method and Apparatus 09/113,071 (ART32) (Jul. 10, 1998) PO8022 15-Jul-97 Image Processing Method and Apparatus 6,398,328 (ART33) (Jul. 10, 1998 PO8497 11-Aug-97 Image Processing Method and Apparatus 09/113,090 (ART34) (Jul. 10, 1998) PO8020 15-Jul-97 Data Processing Method and Apparatus 6,431,704 (ART38) (Jul. 10, 1998 PO8023 15-Jul-97 Data Processing Method and Apparatus 09/113,222 (ART39) (Jul. 10, 1998) PO8504 11-Aug-97 Image Processing Method and Apparatus 09/112,786 (ART42) (Jul. 10, 1998) PO8000 15-Jul-97 Data Processing Method and Apparatus 6,415,054 (ART43) (Jul. 10, 1998) PO7977 15-Jul-97 Data Processing Method and Apparatus 09/112,782 (ART44) (Jul. 10, 1998) PO7934 15-Jul-97 Data Processing Method and Apparatus 6,665,454 (ART45) (Jul. 10, 1998) PO7990 15-Jul-97 Data Processing Method and Apparatus 6,542,645 (ART46) (Jul. 10, 1998) PO8499 11-Aug-97 Image Processing Method and Apparatus 6,486,886 (ART47) (Jul. 10, 1998) PO8502 11-Aug-97 Image Processing Method and Apparatus 6,381,361 (ART48) (Jul. 10, 1998) PO7981 15-Jul-97 Data Processing Method and Apparatus 6,317,192 (ART50) (Jul. 10, 1998 PO7986 15-Jul-97 Data Processing Method and Apparatus 09/113,057 (ART51) (Jul. 10, 1998) PO7983 15-Jul-97 Data Processing Method and Apparatus 6,646,757 (ART52) (Jul. 10, 1998) PO8026 15-Jul-97 Image Processing Method and Apparatus 09/112,752 (ART53) (Jul. 10, 1998) PO8027 15-Jul-97 Image Processing Method and Apparatus 09/112,759 (ART54) (Jul. 10, 1998) PO8028 15-Jul-97 Image Processing Method and Apparatus 6,624,848 (ART56) (Jul. 10, 1998) PO9394 23-Sep-97 Image Processing Method and Apparatus 6,357,135 (ART57) (Jul. 10, 1998 PO9396 23-Sep-97 Data Processing Method and Apparatus 09/113,107 (ART58) (Jul. 10, 1998) PO9397 23-Sep-97 Data Processing Method and Apparatus 6,271,931 (ART59) (Jul. 10, 1998) PO9398 23-Sep-97 Data Processing Method and Apparatus 6,353,772 (ART60) (Jul. 10, 1998) PO9399 23-Sep-97 Data Processing Method and Apparatus 6,106,147 (ART61) (Jul. 10, 1998) PO9400 23-Sep-97 Data Processing Method and Apparatus 6,665,008 (ART62) (Jul. 10, 1998) PO9401 23-Sep-97 Data Processing Method and Apparatus 6,304,291 (ART63) (Jul. 10, 1998) PO9402 23-Sep-97 Data Processing Method and Apparatus 09/112,788 (ART64) (Jul. 10, 1998) PO9403 23-Sep-97 Data Processing Method and Apparatus 6,305,770 (ART65) (Jul. 10, 1998) PO9405 23-Sep-97 Data Processing Method and Apparatus 6,289,262 (ART66) (Jul. 10, 1998) PP0959 16-Dec-97 A Data Processing Method and Apparatus 6,315,200 (ART68) (Jul. 10, 1998) PP1397 19-Jan-98 A Media Device (ART69) 6,217,165 (Jul. 10, 1998) 

1. A digital camera including: an image capture assembly; a housing adapted to locate a roll of print media; a print media transport assembly to transport the print media along a path; and a printhead arranged to print across the path and responsive to the image capture assembly.
 2. A digital camera according to claim 1, wherein the printhead comprises a pagewidth microelectromechanical ink jet printhead.
 3. A digital camera according to claim 1, including; a print media severing assembly located at an exit of the path.
 4. A digital camera according to claim 3, wherein the print media severing assembly comprises a blade mounted upon a worm screw disposed along the exit.
 5. A digital camera according to claim 2, including a recapping mechanism arranged to cap the printhead between printing operations.
 6. A digital camera according to claim 5, wherein the recapping mechanism includes a biasing member arranged to bias a capping portion of the recapping mechanism to a capping position and a solenoid coil arranged to overcome the biasing member during printing operations.
 7. A digital camera according to claim 6, including a processing integrated circuit in communication with the image capture assembly.
 8. A digital camera according to claim 7, wherein the worm screw is driven by a motor controlled by the processing integrated circuit.
 9. A digital camera according to claim 7, wherein the solenoid coil is controlled by the processing integrated circuit.
 10. A digital camera according to claim 4, wherein the print media severing assembly is arranged to increment a counter each time the print media severing assembly operates. 